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+<?xml version='1.0'?>
+<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN"
+                  "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" [
+
+<!ENTITY Evolution "<application>Evolution</application>">
+<!ENTITY GNOME "<application>GNOME</application>">
+<!ENTITY eclipse "<application>Eclipse</application>">
+<!ENTITY Camel "<application>Camel</application>">
+<!ENTITY EPlugin "<application>EPlugin</application>">
+<!ENTITY e-popup-reference SYSTEM "e-popup.xml">
+<!ENTITY e-menu-reference SYSTEM "e-menu.xml">
+<!ENTITY e-config-reference SYSTEM "e-config.xml">
+<!ENTITY e-event-reference SYSTEM "e-event.xml">
+<!ENTITY e-plugin-reference SYSTEM "e-plugin.xml">
+
+<!ENTITY em-popup-reference SYSTEM "em-popup.xml">
+<!ENTITY em-format-reference SYSTEM "em-format.xml">
+
+]>
+<?xml-stylesheet href="sdocbook.css" type="text/css"?>
+
+<book lang="en">
+  <!-- DocBook file was created by LyX 1.3
+  See http://www.lyx.org/ for more information -->
+  <bookinfo>
+    <title>
+      &Evolution; Plugin Development Manual
+    </title>
+    
+    <authorgroup>
+      <corpauthor>
+	Novell, Inc.
+      </corpauthor>
+      <author>
+	<firstname>Michael</firstname><surname>Zucchi</surname>
+      </author>
+    </authorgroup>
+
+    <copyright>
+      <year>2004</year>
+      <holder>Novell, Inc.</holder>
+    </copyright>
+
+  </bookinfo>
+
+  <preface id="preface">
+    <title>Preface</title>
+
+    <para>
+      This document is work-in-progress.  Its structure and design is still as
+      fluid as the underlying strucutre and design of some parts of EPlugin.
+      There's no guarantee it will be updated at regular intervals,
+      particularly this version.
+    </para>
+    <para>
+      The API documentation is currently generated using the Linux kernel-doc
+      script.  The stylesheets used to generate the HTML you're seeing seems to
+      have bugs which duplicates some sections.  It is also ugly and difficult
+      to navigate.
+    </para>
+
+    <sect1>
+      <title>Conventions</title>
+      <para>
+	The following conventions are used in the manual ... (insert details
+	here).
+      </para>
+      <sect2>
+	<title>XML Annotation</title>
+	<para>
+	  XML definitions are annotated with BNF-style markers to indicate
+	  alternative (|), multiples (* or +), and optional (?) items.  If no
+	  annotation is present then the item must be present once.
+	</para>
+	<variablelist>
+	  <varlistentry>
+	    <!-- is symbol the right one here? -->
+	    <term><symbol>|</symbol></term>
+	    <listitem>
+	      <simpara>Indicates an alternative option.  Only one of the items
+		separated by <symbol>|</symbol> is to be chosen.
+	      </simpara>
+	    </listitem>
+	  </varlistentry>
+	  <varlistentry>
+	    <term><symbol>*</symbol></term>
+	    <listitem>
+	      <simpara>Following an item, <symbol>*</symbol> indicates the item
+		may occur any number of times, including no times (0 or more
+		multiple).
+	      </simpara>
+	    </listitem>
+	  </varlistentry>
+	  <varlistentry>
+	    <term><symbol>+</symbol></term>
+	    <listitem>
+	      <simpara>Following an item, <symbol>+</symbol> indicates the item
+		must occur at least once, but may occur more than ones (1 or
+		more multiple).
+	      </simpara>
+	    </listitem>
+	  </varlistentry>
+	  <varlistentry>
+	    <term><symbol>?</symbol></term>
+	    <listitem>
+	      <simpara>Following an item, <symbol>?</symbol> indicates the item
+		may occur at most once, if present (0 or 1 times).
+	      </simpara>
+	    </listitem>
+	  </varlistentry>
+	</variablelist>
+      </sect2>
+    </sect1>
+
+  </preface>
+
+  <part id="informational">
+    <title>
+      EPlugin
+    </title>
+    <chapter>
+      <title>
+	Introduction
+      </title>
+      <para>
+	This book aims to be a comprehensive technical manual for the
+	development of plugins for &Evolution;, a personal information manager
+	for &GNOME;.
+      </para>
+      <para>
+	Up-to, and including, &Evolution; version 2.0, &Evolution; contained
+	limited extensibility interfaces. There were only two ways to extend
+	&Evolution;; by implementing a new top-level component, or by
+	implementing a &Camel; provider. When implementing a top-level component,
+	there was still little integration, and in effect it was merely a more
+	complex way of writing a separate &GNOME; application. &Camel; providers
+	were only designed to be e-mail storage backends, so were of limited
+	use for general extensibility. Despite this, both mechanisms were used
+	for example for the Exchange Connector, although the system made the
+	integration clumsy and difficult.
+      </para>
+      <para>
+	This lack of extensibility has severaly stifled external developer
+	contributions by forcing any extensions to be considered as core
+	features. &Evolution; being a commercial product, it has tight usability
+	and quality requirements that limits the ability to experiment with
+	the core feature set in this way. As a result, very few lines of code
+	or new features have been implemented by external contributors.
+      </para>
+      <para>
+	One of the major goals for the 2.2 release was to implement an
+	extensibility system, given the working name of EPlugin, which must
+	provide a frame-work for both providing extensibility hooks, and for
+	extending the functionality of &Evolution;.
+      </para>
+      <sect1>
+	<title>
+	  Plugin System
+	</title>
+	<para>
+	  Any plugin system will generally have a number of goals:
+	</para>
+	<itemizedlist>
+	  <listitem>
+	    <simpara>
+	      Provide a language independent invocation mechanism
+	    </simpara>
+	  </listitem>
+	  <listitem>
+	    <simpara>
+	      Allow extension of parts of the user interface and processing elements
+	    </simpara>
+	  </listitem>
+	  <listitem>
+	    <simpara>
+	      Require minimal extra or foreign code to implement in the core application
+	    </simpara>
+	  </listitem>
+	  <listitem>
+	    <simpara>
+	      Require minimal interface code to implement the extensions
+	    </simpara>
+	  </listitem>
+	  <listitem>
+	    <simpara>
+	      Not to impact performance or increase resource usage unduly
+	    </simpara>
+	  </listitem>
+	  <listitem>
+	    <simpara>
+	      Versioning
+	    </simpara>
+	  </listitem>
+	  <listitem>
+	    <simpara>
+	      Be able to be extended itself fairly easily.
+	    </simpara>
+	  </listitem>
+	</itemizedlist>
+	<para>
+	  EPlugin manages to fulfill these goals in most cases. EPlugin isn't a
+	  single object or interface in itself, although there is an object
+	  titled EPlugin, it is a synergistic
+	  <footnote><simpara>I've always wanted to use
+	      <emphasis>synergistic</emphasis> in a sentence since
+	      I read it on the back of the Commodore 64 Users
+	      Guide.</simpara></footnote>
+	  collection of integrated and
+	  continually evolving objects which work together to achieve these
+	  goals (and that will definitly be the end of the MarketSpeak). It
+	  consists of a loader to invoke extension callbacks, hooks to resolve
+	  these callbacks, targets to identify context, and managers which are
+	  used by the core code to provide functionality and merging points for
+	  the extensions.
+	</para>
+	<para>
+	  EPlugin's design was inspired and influenced by the &eclipse;
+	  project. It aims at a lower target however, so it was able more easily
+	  implemented in a practical time-frame.
+	</para>
+	<para>
+	  &EPlugin; was chosen as an approach to the problem of adding
+	  scriptability to &Evolution;.  Instead of just linking to Perl, or
+	  Python, or even Mono by itself an approach was taken which focuses on
+	  the application end of the system.  So instead of making every part
+	  of the application export its functionality and have to deal with
+	  whatever script engine is present, EPlugin addresses the hooking part
+	  of the equation in a language-independent manner.  It also attemps to
+	  do it in a way which doesn't impact on the application development
+	  either.
+	</para>
+	<para>
+	  The EPlugin world is awash with its own language. The next few
+	  sections will introduce the basic plugin nomenclature and high-level
+	  view of this world.
+	</para>
+
+      </sect1>
+
+      <sect1>
+	<title>
+	  Loaders
+	</title>
+	<para>
+	  The core of EPlugin is a light-weight object loader and callback
+	  invocation system. Because of the varied calling conventions of
+	  different languages, and to reduce the overhead of the plugin system
+	  itself, all callbacks only receive and return a single argument. By
+	  using structures to pass complex arguments, native C plugins require
+	  no extra overhead, and marshalling details are moved into the plugin
+	  implementation itself where required. It also simplifies memory
+	  management issues significantly. For example, the C plugin handler
+	  merely loads a shared library using GModule, and resolves a symbol by
+	  name; and is so all of 50 lines of code, total. The loaders are the
+	  only modules which need to interace with non-native code or
+	  conventions.
+	</para>
+	<para>
+	  The other task of the plugin core is to load XML definitions of the
+	  plugins. Extension hooks are registered with the plugin core before
+	  the plugins are scanned, and are automatically instantiated to load
+	  each definition appropriately as they are encountered.
+	</para>
+	<para>
+	  At each layer, a level of indirection is used so that new loaders and
+	  new hooks can be added transparently, and extend the plugin
+	  definition freely with any information they require.
+	</para>
+      </sect1>
+
+      <sect1>
+	<title>
+	  Hooks
+	</title>
+	<para>
+	  The hooks
+	  <footnote>
+	    <para>A hook is something you can hang your stuff on.</para>
+	  </footnote>
+	  which are registered with the loader provide meta-data for
+	  the management implementation layer for extending it at
+	  run-time. Their primary
+	  functions are to load the detail of the XML plugin definition, map it
+	  to the implementation, and marshal the implementation callbacks to
+	  the common plugin interface. How they do this depends on the
+	  implementation itself, and ranges from registering factory methods to
+	  simply adding the items directly.
+	</para>
+	<para>
+	  In most cases the physical object need not be loaded until the
+	  callback is invoked, since the plugin definitions provide enough
+	  contextual information to build the interface or determine when they
+	  need to be invoked.
+	</para>
+      </sect1>
+
+      <sect1>
+	<title>
+	  Managers
+	</title>
+	<para>
+	  Managers
+	  <footnote>
+	    <para>
+	      Unlike real managers, these are the ones that do the heavy lifting.
+	    </para>
+	  </footnote>
+	  provide tools for the core code to extend itself at specific
+	  points, and in many cases are the objects used directly in the code
+	  to implement core features. In other cases they simply provide the
+	  hooks with an entry point into &Evolution;. For example, for the main
+	  menu hook, the manager is a thin layer to BonoboUI. On the other
+	  hand, EPopup is a complete implementation of a popup menu management
+	  system which was already used in &Evolution; 2.0. Some managers are
+	  one-off objects used as constructors for other objects, others are
+	  view-dependent, and some are static objects, such as the Event
+	  routers.
+	</para>
+      </sect1>
+
+      <sect1>
+	<title>
+	  Items
+	</title>
+	<para>
+	  Each manager uses a number of items to describe the object they
+	  control or create. The items are added to each manager instance from
+	  the plugins or from core code. The items from all of these sources
+	  are then merged together when required and processed accordingly. For
+	  example, menu items are merged into a tree of GtkMenus. Events on the
+	  other hand are simply ordered and then invoked in the order of their
+	  priority. Items are part of the manager implementation, and in
+	  &EPlugin; they are all extensible objects too, which the hooks use to
+	  perform mapping to the plugin. Items may be extended by code hooking
+	  into the implementation, either the plugin hooks, or the core code.
+	</para>
+      </sect1>
+
+      <sect1>
+	<title>
+	  Targets
+	</title>
+	<para>
+	  Targets
+	  <footnote><para>Think of a target as the target of
+	      interest.</para></footnote>
+	  are view or component specific context objects. They contain
+	  enough information to be used as stand-alone contexts to implement
+	  callbacks for both core functions and plugin hooks. For example for
+	  the mail view, a select target contains a folder and a list of
+	  selected messages. An attachment (part) target contains the
+	  &Camel; representation of the part and the mime-type for
+	  that part. Targets are part of the manager implementation and are
+	  extended by subclassing the manager.
+	</para>
+      </sect1>
+    </chapter>
+
+    <chapter id="plugin-loaders">
+      <title>
+	Plugin Loaders
+      </title>
+      <para>
+	Plugin loaders implement a hool to a new language, or loading system in the
+	plugin system.  The actual binding of new languages to the plugin system or
+	other parst of &Evolution;s api's are beyond the scope of this
+	document, some languages make this easier than others.
+      </para>
+      <sect1 id="plugin-loaders-base">
+	<title>
+	  Base Plugin
+	</title>
+	<para>
+	  The <link linkend="API-struct--EPlugin">EPlugin base class</link>
+	  is an abstract class which provides the basic services for plugin
+	  implementations. The main services are:
+	  <itemizedlist>
+	    <listitem><simpara>Resolve plugin type and instantiate an EPlugin
+		object to represent and manage it.</simpara></listitem>
+	    <listitem><simpara>Load the base structure of the XML plugin
+		definition files.</simpara></listitem>
+	    <listitem><simpara>Resolve plugin hook types and instantiate a
+		EPluginHook to represent and manage it.</simpara></listitem>
+	    <listitem><simpara>Provide a simple, language-independent api for
+		invoking plugin callbacks</simpara></listitem>
+	    <listitem><simpara>Provide I18N context for plugins.</simpara></listitem>
+	    <listitem><simpara>Some simple static helper methods to simplify each
+		implementing class.</simpara></listitem>
+	  </itemizedlist>
+	  See the <xref linkend="REF-EPlugin"/> for
+	  these details.
+	</para>
+
+	<sect2 id="plugin-loaders-definition">
+	  <title>Definition of a Plugin</title>
+	  <para>
+	    The base plugin XML definition.  Subclasses of EPlugin extend this
+	    basic structure with additional parameters or elements as they
+	    require.
+	  </para>
+	  <para>
+	    Note that there may be any number of <sgmltag>e-plugin</sgmltag>
+	    elements in a given plugin file, this may be used to simplify
+	    distribution of plugin packages.
+	  </para>
+	  <programlisting>
+	    <![CDATA[
+<?xml version="1.0">
+<e-plugin-list>
+  <e-plugin
+    type="loader type"
+    domain="translation domain" ?
+    name="plugin name"
+    ...>
+    <description>long description</description> ?
+    <hook
+      class="hook class"
+      ...>
+    ...
+    </hook> +
+  </e-plugin> +
+</e-plugin-list>]]></programlisting>
+	  <variablelist>
+	    <varlistentry>
+	      <term><parameter>type</parameter></term>
+	      <listitem>
+		<simpara>
+		  The type name of the plugin loader.  Currently <link
+		    linkend="plugin-loaders-lib">shlib</link> and <link
+		    linkend="plugin-loaders-mono">mono</link> are the only
+		  supported values.  If no known handler is registered for this
+		  type, the plugin definition is silently ignored.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>domain</parameter></term>
+	      <listitem>
+		<simpara>
+		  The translation domain for this plugin, as passed to the
+		  <function>dcgettext</function> call of the gettext package.
+		  If not supplied then the default application domain is used
+		  (i.e. &quot;evolution&quot;).  This is used to translate
+		  translatable strings for display.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>name</parameter></term>
+	      <listitem>
+		<simpara>
+		  A short name for the plugin.  &quot;Bob's Wonder
+		  Extender&quot; might be suitable.  This value will be
+		  translated.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>description</parameter></term>
+	      <listitem>
+		<simpara>
+		  A longer description of the plugin's purpose. This value will be
+		  translated.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>hook</parameter></term>
+	      <listitem>
+		<simpara>
+		  This is a list of all of the hooks that this plugin wishes to
+		  hook into.  See the <link linkend="plugin-hooks">Plugin
+		    Hooks</link> section for the details of the basic hook
+		  types defined.
+		</simpara>
+		<simpara>
+		  The hook <parameter>class</parameter> is resolved using the
+		  registered hook types, and if none can be found, or a version
+		  mismatch occurs, then the hook is silently ignored.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	  </variablelist>
+	</sect2>
+      </sect1>
+
+      <sect1 id="plugin-loaders-lib">
+	<title>
+	  Shared Library Loader
+	</title>
+	<para>
+	  The shared library loader <link
+	    linkend="API-struct--EPluginLib">EPluginLib</link> implements a
+	  concrete EPlugin type which loads GNU shared libraries via the
+	  GModule api.  It simply resolves symbols directly from the loaded
+	  shared object and invokes them with the same arguments as the
+	  <link linkend="API-e-plugin-invoke">e_plugin_invoke</link> method.
+	</para>
+
+	<sect2 id="plugin-loaders-lib-definition">
+	  <title>Definition</title>
+	  <para>The shared library loader only requires one extra parameter in
+	    the base plugin definition.
+	  </para>
+	  <programlisting>
+	    <![CDATA[
+<e-plugin
+  ...
+  type="shlib"
+  location="/full/path/name.so"
+  ...
+  <hook class="...">
+   ...
+</e-plugin>]]></programlisting>
+	  <variablelist>
+	    <varlistentry>
+	      <term><parameter>type</parameter></term>
+	      <listitem>
+		<simpara>
+		  The type name of the shared library plugin is
+		  <constant>shlib</constant>.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>location</parameter></term>
+	      <listitem>
+		<simpara>
+		  The location parameter contains
+		  the full path-name of a shared object to load.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	  </variablelist>
+	</sect2>
+
+	<sect2 id="plugin-loaders-lib-invocation">
+	  <title>Invocation</title>
+	  <simplesect>
+	    <title>Function specification
+	    </title>
+	    <para>Where a function spec is required in a plugin
+	      hook definition, it should simply be the full name of an
+	      exported symbol in the shared object.
+	    </para>
+	  </simplesect>
+	  <simplesect>
+	    <title>Callback signature</title>
+	    <funcsynopsis><funcprototype>
+		<funcdef>void * <function>function</function></funcdef>
+		<paramdef>EPlugin * <parameter>ep</parameter></paramdef>
+		<paramdef>void * <parameter>data</parameter></paramdef>
+	      </funcprototype></funcsynopsis>
+	    <variablelist>
+	      <varlistentry>
+		<term><function>function</function></term>
+		<listitem>
+		  <simpara>
+		    The callback function.
+		  </simpara>
+		</listitem>
+	      </varlistentry>
+	      <varlistentry>
+		<term><parameter>ep</parameter></term>
+		<listitem>
+		  <simpara>
+		    The container EPlugin representing this plugin.
+		  </simpara>
+		</listitem>
+	      </varlistentry>
+	      <varlistentry>
+		<term><parameter>data</parameter></term>
+		<listitem>
+		  <simpara>
+		    Hook context data.  It is part of the hook's api to specify
+		    the type of this pointer.
+		  </simpara>
+		</listitem>
+	      </varlistentry>
+	      <varlistentry>
+		<term><returnvalue>return value</returnvalue></term>
+		<listitem>
+		  <simpara>
+		    Return data.  It is part of the hook's api to specify the
+		    type of this pointer.
+		  </simpara>
+		</listitem>
+	      </varlistentry>
+	    </variablelist>
+	  </simplesect>
+	</sect2>
+      </sect1>
+
+      <sect1 id="plugin-loaders-mono">
+	<title>
+	  Mono Assembly Loader
+	</title>
+	<para>
+	  The mono assembly loader <link
+	    linkend="API-struct--EPluginMono">EPluginMono</link> implements a
+	  concrete EPlugin type which loads C# assemblies using Mono.  Apart
+	  from loading the assembly, it can optionally instantiate a class to
+	  implement the callback or invoke static methods directly.
+	</para>
+
+	<sect2 id="plugin-loaders-mono-definition">
+	  <title>Definition</title>
+	  <para>The mono assembly loader needs the name of the assembly and
+	    optionally the name of the class for handling the callbacks.
+	  </para>
+	  <programlisting>
+	    <![CDATA[
+<e-plugin
+  ...
+  type="mono"
+  location="/full/path/name.dll"
+  handler="PluginClass" ?
+  ...
+  <hook class="...">
+   ...
+</e-plugin>]]></programlisting>
+	  <variablelist>
+	    <varlistentry>
+	      <term><parameter>type</parameter></term>
+	      <listitem>
+		<simpara>
+		  The type name of a mono assembly plugin is
+		  <constant>mono</constant>.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>location</parameter></term>
+	      <listitem>
+		<simpara>
+		  The location parameter contains
+		  the full path-name of an assembly to load.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>handler</parameter></term>
+	      <listitem>
+		<simpara>
+		  If supplied, the handler contains the fully qualified name of
+		  the class which handles all callbacks for this plugin.  If a
+		  handling class is used, then the function specifications
+		  become relative to this class.
+		</simpara>
+		<simpara>
+		  This class will be
+		  instantiated once upon the first callback invocation, and
+		  remain active for the life of the plugin (or application).
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	  </variablelist>
+	</sect2>
+
+	<sect2 id="plugin-loaders-mono-invocation">
+	  <title>Invocation</title>
+	  <simplesect>
+	    <title>Function specification
+	    </title>
+	    <para>If no <parameter>handler</parameter> class is specified, then
+	      the function specification must match a static method in the
+	      assembly.  This is passed to <function>mono_method_desc_new</function>
+	      and <function>mono_method_desc_search_in_image</function>,
+	      typically <function>FunctionName(intptr)</function>.
+	    </para>
+	    <para>
+	      If the handler is specified, then the function specification is
+	      relative to the handler class.  This is passed to
+	      <function>mono_method_desc_new</function> and
+	      <function>mono_method_desc_search_in_class</function>, typically
+	      <function>:MethodName(intptr)</function>.
+	    </para>
+	  </simplesect>
+	  <simplesect>
+	    <title>Callback signature</title>
+	    <funcsynopsis><funcprototype>
+		<funcdef>IntPtr <function>function</function></funcdef>
+		<paramdef>IntPtr <parameter>data</parameter></paramdef>
+	      </funcprototype></funcsynopsis>
+	    <variablelist>
+	      <varlistentry>
+		<term><function>function</function></term>
+		<listitem>
+		  <simpara>
+		    The callback method.
+		  </simpara>
+		</listitem>
+	      </varlistentry>
+	      <varlistentry>
+		<term><parameter>data</parameter></term>
+		<listitem>
+		  <simpara>
+		    The hook context data.  This is a pointer to unmanaged data, and it is up-to the plugin to interpret this
+		    data right now, although some helper binding classes are
+		    planned.  FIXME: hook-up when they and doco are done.
+		  </simpara>
+		</listitem>
+	      </varlistentry>
+	      <varlistentry>
+		<term><returnvalue>return value</returnvalue></term>
+		<listitem>
+		  <simpara>
+		    The callback return data.  It is up to the hook's api to
+		    define the type of this pointer.  It may be a simple boxed
+		    value type, or a memory pointer allocated in unmanaged memory (e.g. a
+		    GObject handle or a CamelObject cobject value).
+		  </simpara>
+		</listitem>
+	      </varlistentry>
+	    </variablelist>
+	  </simplesect>
+	</sect2>
+      </sect1>
+
+    </chapter>
+
+    <chapter id="plugin-hooks">
+      <title>
+	Plugin Hooks
+      </title>
+      <para>
+	This chapter will introduce the available plugin hook types. A given
+	plugin can hook into any of these hooks any number of times. Some refer
+	to specific instances of objects and others are implicitly defined.
+      </para>
+      <para>
+	By design, there is considerable similarity and orthogonality amongst
+	all of the various hook types and management objects.
+      </para>
+      <sect1 id="plugin-hooks-popup">
+	<title>
+	  Popup Menus
+	</title>
+	<para>
+	  The popup menu hook lets you hook into any of the context menus in
+	  &Evolution;, by name and context. Complex, dynamic, and multi-level
+	  menus are created on the fly by merging the items for a given menu as
+	  it is being shown. Each component provides its own context targets to
+	  self-describe the situation under which the menu is invoked. Plugins
+	  and core code alike are then invoked at the user's direction. The
+	  popup manager and all context data lives as long as the menu and
+	  until a choice is made, simplifying memory management.
+	</para>
+	<para>
+	  The menu is merged from multiple plugins and core application code by
+	  using a simple lexiographical sort of an absolute path to the menu
+	  item. This merged list is then scanned and expanded into a tree of
+	  menus. Individual items can be hidden or inactive based on the target
+	  and a simple mask which is defined by the component itself. A rich
+	  collection of menu item types are possible, from simple, to
+	  checkboxes or images. The popup code is simple, and easy to use, and
+	  simplifies the use of popup menu's in the core application anyway,
+	  that they are pluggable is a free-bonus.
+	</para>
+	<sect2>
+	  <title>Defining a popup hook</title>
+	  <para>
+	    Not sure if this fits here as such.  Probably temporary placeholder.
+	  </para>
+	  <programlisting>
+	    <![CDATA[
+<hook class="com.ximian.evolution.mail.popup:1.0">
+ <menu id="menuid" target="targettype">
+  <item
+   type="item | toggle | radio | image | submenu | bar"
+   active ?
+   path="foo/bar"
+   label="menu text"
+   icon="icon name" ?
+   visible="target mask" ?
+   enable="target mask" ?
+   activate="function spec"/> *
+ </menu> *
+</hook>]]></programlisting>
+	  <!-- this is all too bloody verbose, is there a better way? -->
+	  <para>
+	    <emphasis>Need to define menu tag</emphasis>
+	  </para>
+	  <variablelist>
+	    <varlistentry>
+	      <term><parameter>type</parameter></term>
+	      <listitem>
+		<simpara>
+		  The menu item type.  The type maps directly to the
+		  corresponding EPopupItem types.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>active</parameter></term>
+	      <listitem>
+		<simpara>
+		  If present, then radio or toggle menu items are active when
+		  first shown.  After the first instantiation, they will
+		  remember their active state.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>path</parameter></term>
+	      <listitem>
+		<simpara>
+		  A '/' separated path used to position the item within menu
+		  and in the right submenu.  Each menu and plugin should
+		  define how its menu's are layed out so other plugins can
+		  determine what value to use here.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>label</parameter></term>
+	      <listitem>
+		<simpara>
+		  The text to be displayed on the menu item.  This will be
+		  translated based on the plugin translation domain.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>icon</parameter></term>
+	      <listitem>
+		<simpara>
+		  The name of a gnome-icon-theme standard icon, or the full
+		  path-name of an icon image to use as menu item icon.  This
+		  will be blank if not supplied.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>visible</parameter></term>
+	      <listitem>
+		<simpara>
+		  A comma separated list of mask enumeration values used to
+		  define when this item is shown.  What values are valid
+		  depend on the menu hook class of the menu being hooked
+		  onto.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>enable</parameter></term>
+	      <listitem>
+		<simpara>
+		  A comma separated list of mask enumeration values used to
+		  define when this item is enabled.  What values are valid
+		  depend on the menu hook class of the menu being hooked
+		  onto.  This is currently unimplemented.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>activate</parameter></term>
+	      <listitem>
+		<simpara>
+		  A plugin-type specific function specification.  This
+		  function will be resolved and called when the menu item is
+		  activated.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	  </variablelist>
+	</sect2>
+	<sect2>
+	  <title>Merging Plugin Items</title>
+	  <para>
+	    A very simple algorithm is used to form the menu by merging the
+	    plugin's menu items with the system menu items for a given menu.
+	    What follows is a simple example of how this is done.  It will be
+	    demonstrated using a simplified menu from the message-list, as used
+	    in the &Evolution; Mail component, and a simple plugin which adds a
+	    single menu item and menu separator into the middle of the menu,
+	    when appropriate.
+	  </para>
+	  <para>
+	    When the application wishes to show a specific popup menu, it
+	    creates a new EPopup object with a unique menu id to manage it.  It
+	    adds all of the items it wishes to add to the menu (see "Builtin
+	    Items" in the following diagrams).  The application then asks for
+	    the menu to be created.  The menu building
+	    process adds all of the menu items from all plugins that target
+	    this specific menu into a flat list, discarding those which don't
+	    match the current Target qualifications.  The result is then
+	    sorted using a simple ASCII sort, and then a menu built from the
+	    remaining items.  This is probably best described by some diagrams.
+	  </para>
+	  <para>
+	    The following two diagrams show how a popup menu is automatically
+	    customised depending on the context.  On the left of each diagram
+	    are all of the menu items which apply to the example menu.  The
+	    menu label, with the qualifiers listed underneath, with the menu
+	    item path along-side.  On the right-hand side of each diagram is
+	    the result of:
+	  </para>
+	  <itemizedlist>
+	    <listitem><simpara>Selecting items based on the target
+		qualifiers</simpara></listitem>
+	    <listitem><simpara>Sorting the remaining items based on their
+		path.</simpara></listitem>
+	    <listitem><simpara>Building this sorted list into a
+		menu.</simpara></listitem>
+	  </itemizedlist>
+
+	  <para>
+	    The actual list of target qualifiers are defined by the application
+	    itself.  Generally a specific menu will have only one possible
+	    target, and a list of matching target qualifiers.  The example
+	    shows how a plugin can insert a menu item anwhere it wishes in the
+	    menu system.  Submenus are also supported, and they work in exactly
+	    the same manner, with / characters used to separate submenu paths.
+	    A submenu must sort into the position immediately before the
+	    definition of its items.
+	  </para>
+
+	  <figure id="e-popup-merge-1">
+	    <title>Merging a menu with many items selected.</title>
+	    <mediaobject>
+	      <imageobject>
+		<imagedata fileref="images/e-popup-merge-1.pic" format="PIC" />
+	      </imageobject>
+	      <imageobject>
+		<imagedata fileref="images/e-popup-merge-1.eps" format="EPS"/>
+	      </imageobject>
+	      <imageobject>
+		<imagedata fileref="images/e-popup-merge-1.png" format="PNG"/>
+	      </imageobject>
+	      <textobject>
+		<phrase>Showing how a display list of menu items is selected
+		  and then sorted for display.</phrase>
+	      </textobject>
+	    </mediaobject>
+	  </figure>
+
+	  <para>
+	    The first diagram shows when the target qualifiers are
+	    <parameter>many</parameter>, and
+	    <parameter>mark_unread</parameter>.  The menu items which operate
+	    on only one selected message are not shown.  Similarly for those
+	    able to be marked as unread (i.e. they are currently read).
+	  </para>
+
+	  <figure id="e-popup-merge-2">
+	    <title>Merging a menu with one item selected.</title>
+	    <mediaobject>
+	      <imageobject>
+		<imagedata fileref="images/e-popup-merge-2.pic" format="PIC"/>
+	      </imageobject>
+	      <imageobject>
+		<imagedata fileref="images/e-popup-merge-2.eps" format="EPS"/>
+	      </imageobject>
+	      <imageobject>
+		<imagedata fileref="images/e-popup-merge-2.png" format="PNG"/>
+	      </imageobject>
+	      <textobject>
+		<phrase>Showing how a display list of menu items is selected
+		  and then sorted for display with different qualifiers.</phrase>
+	      </textobject>
+	    </mediaobject>
+	  </figure>
+
+	  <para>
+	    This diagram shows when the target qualifiers are
+	    <parameter>one</parameter>, and
+	    <parameter>mark_read</parameter>.  The menu items which operate
+	    on only many selected messages are not shown.  Similarly for those
+	    able to be marked as read.
+	  </para>
+	</sect2>
+      </sect1>
+
+      <sect1 id="plugin-hooks-menu">
+	<title>
+	  Main menus
+	</title>
+	<para>
+	  The main menu hook lets you hook into various main menus in
+	  &Evolution;, based on the current active view (component). The system
+	  works by piggy-backing on the existing use of the BonoboUI menu
+	  system used by all of the &Evolution; components. Bonobo handles the
+	  menu merging and user input, and the hook resolves the verb being
+	  invoked and redirects it to the plugin. Each view defines a single
+	  target which describes the appropriate context. For the Mail view,
+	  this is the current folder and currently selected message(s).
+	</para>
+	<para>
+	  Each view keeps track of its own manager object. When it is
+	  (de)activated, it also (de)activates the management object which
+	  dynamically adds and removes the menu items from the
+	  BonoboUIContainer via a supplied BonoboUI XML definition file
+	  &lt;perhaps it should embed the bonobouixml&gt;. If the target
+	  changes, the view lets the manager know, and it updates the
+	  visibility and sensitivity of objects appropriately, allowing
+	  reasonably dynamic user-interfaces to be managed automatically. The
+	  plugin itself isn't loaded until the menu item in question is invoked
+	</para>
+	<para>
+	  Simple menu items and toggle menu items are supported currently.
+	  Also, because actual menu display is driven by BonoboUI, then toolbar
+	  items can also be added using this mechanism.
+	</para>
+	<sect2>
+	  <title>Defining a menu hook</title>
+	  <para>
+	    Not sure if this fits here as such.  Probably temporary placeholder.
+	  </para>
+	  <programlisting>
+	    <![CDATA[
+<hook class="com.ximian.evolution.mail.bonoboMenu:1.0">
+ <menu id="menuid" target="targettype"
+  <ui file="/path/to/bonobo-ui-menu-definition.xml"> +
+  <item
+   type="item | toggle | radio"
+   active ?
+   path="/commands/FooBar"
+   verb="FooBar"
+   visible="target mask" ?
+   enable="target mask" ?
+   activate="function spec"/> *
+ </menu> *
+</hook>]]></programlisting>
+	  <para>
+	    <emphasis>Need to define menu tag</emphasis>
+	  </para>
+	  <variablelist>
+	    <varlistentry>
+	      <term><parameter>ui</parameter></term>
+	      <listitem>
+		<simpara>
+		  The <parameter>ui</parameter> element contains a filename of the
+		  BonoboUI XML menu definition to load when the view is activated.  Any number of
+		  <parameter>ui</parameter> elements may be defined, and they
+		  are all loaded.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+
+	    <varlistentry>
+	      <term><parameter>type</parameter></term>
+	      <listitem>
+		<simpara>
+		  The menu item type.  The type maps directly to the
+		  corresponding EMenuItem types.
+		  <parameter>radio</parameter> is currently not implemented.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>active</parameter></term>
+	      <listitem>
+		<simpara>
+		  If present, then radio or toggle menu items are active when
+		  first shown.  After the first instantiation, they will
+		  remember their active state.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>path</parameter></term>
+	      <listitem>
+		<simpara>
+		  The BonoboUI element path corresponding to this menu item.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>verb</parameter></term>
+	      <listitem>
+		<simpara>
+		  The BonoboUI verb corresponding to the item to be listened to.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>visible</parameter></term>
+	      <listitem>
+		<simpara>
+		  A comma separated list of mask enumeration values used to
+		  define when this item is shown.  What values are valid
+		  depend on the menu hook class of the menu being hooked
+		  onto.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>enable</parameter></term>
+	      <listitem>
+		<simpara>
+		  A comma separated list of mask enumeration values used to
+		  define when this item is sensitive.  What values are valid
+		  depend on the menu hook class of the menu being hooked
+		  onto.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>activate</parameter></term>
+	      <listitem>
+		<simpara>
+		  A plugin-type specific function specification.  This
+		  function will be resolved and called when the menu item is
+		  activated.  The funciton's parameters will depend on the type
+		  of menu item being invoked.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	  </variablelist>
+	</sect2>
+	<sect2>
+	  <title>Merging Plugin Items</title>
+	  <para>
+	    Merging is performed by BonoboUI, and the source of the menu data
+	    is defined by the <parameter>ui</parameter> file.
+	  </para>
+	</sect2>
+      </sect1>
+
+      <sect1 id="plugin-hooks-config">
+	<title>
+	  Configuration Pages and Wizards
+	</title>
+	<para>
+	  Configuration pages are somewhat more complex than any of the other
+	  types of hookable object. This is reflected in the complexity of the
+	  items and callbacks involved.
+	</para>
+	<para>
+	  Essentially, the EConfig object is used in combination to both
+	  instrument existing windows and building new content.  Each
+	  configuration window comprises of several basic elements with some
+	  minor variations allowed.  It consists of a number of pages in a
+	  specific order, each containing a number of titled sections in a specific
+	  order, each containing a number of items.  The variations are that
+	  the top-level widget may be a GtkNotebook or a GnomeDruid; and each
+	  section may instrument a GtkBox, or a GtkTable.  The definition of
+	  the available hooks will define what form they take.
+	</para>
+	<para>
+	  The EConfig manager uses the description of all the items supplied to
+	  it to build the complete window.  It can also drive various aspects
+	  of the UI, such as navigating through a druid or handling
+	  instant-apply vs. modify-and-save dialogues.
+	</para>
+	<figure id="e-config-flow">
+	  <title>Event and Data Flow in EMConfig</title>
+	  <mediaobject>
+	    <imageobject>
+	      <imagedata fileref="images/e-config-flow.pic" format="PIC"/>
+	    </imageobject>
+	    <imageobject>
+	      <imagedata fileref="images/e-config-flow.eps" format="EPS"/>
+	    </imageobject>
+	    <imageobject>
+	      <imagedata fileref="images/e-config-flow.png" format="PNG"/>
+	    </imageobject>
+	    <textobject>
+	      <phrase>The flow of information and control signals in the
+		configuration management object.</phrase>
+	    </textobject>
+	  </mediaobject>
+	</figure>
+
+	<sect2>
+	  <title>Defining a configuration page hook</title>
+	  <para>
+	    Not sure if this fits here as such.  Probably temporary placeholder.
+	  </para>
+	  <programlisting>
+	    <![CDATA[
+<hook class="com.ximian.evolution.mail.bonoboMenu:1.0">
+ <group
+  id="window id"
+  target="targettype"
+  commit="function spec"?
+  abort="function spec"?>
+  <item
+   type="book | druid | page | page_start | page_finish | section | section_table | item"
+   path="/absolute/path"
+   label="name" | factory="function  spec"
+  /> *
+ </menu> *
+</hook>]]></programlisting>
+	  <para>
+	    <emphasis>Need to define group tag</emphasis>
+	  </para>
+	  <variablelist>
+	    <varlistentry>
+	      <term><parameter>type</parameter></term>
+	      <listitem>
+		<simpara>
+		  The menu item type.  The type maps directly to the
+		  corresponding EConfigItem types.  Only one of
+		  <parameter>book</parameter> and <parameter>druid</parameter>
+		  may be supplied for the entire configuration page, and this
+		  will usually already be defined by the application.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>path</parameter></term>
+	      <listitem>
+		<simpara>
+		  The path to the configuration item in question.  This is a
+		  simple string that when sorted using an ASCII sort will place
+		  the items in the right order.  That is, sections before items
+		  before pages before the root object.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>label</parameter></term>
+	      <listitem>
+		<simpara>
+		  The textual label of this item.  This may only be supplied
+		  for the section and page types.  For sections it will be the
+		  section frame text.  For pages this will be the druid page
+		  title or the notebook tab text.  If a
+		  <parameter>factory</parameter>is supplied then this value is
+		  not used.  This will be translated based on the plugin
+		  translation domain.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>factory</parameter></term>
+	      <listitem>
+		<simpara>
+		  If supplied, the factory method used to create the GtkWidget
+		  elements for this configuration item.  Factories may be
+		  supplied for any of the item types.  If no
+		  <parameter>label</parameter> is set then the
+		  <parameter>factory</parameter> must be set.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	  </variablelist>
+	</sect2>
+	<sect2>
+	  <title>Generating Configuration Pages</title>
+	  <para>
+	    Configuration items essentially spam 3 dimensions, but are
+	    merged in a similar fashion to the way Popup items are merged.  The
+	    main difference is that there are no target qualifiers used to
+	    select which items are shown, it is up to the item factory to
+	    either create or not create the item as it sees fit.  The EConfig
+	    manager takes care of the rest, including removing un-used sections
+	    or pages.
+	  </para>
+	  <para>
+	    All items for a given configuration screen are converted into a
+	    list and sorted based on the <parameter>path</parameter>.  The
+	    configuration builder then goes through each item, creating
+	    container widgets or calling factories as required.  If a given
+	    page or section is empty, then it is removed automatically.  This
+	    process isn't only a one-off process.  For certain complex
+	    configuration screens, items or even pages and sections need to be
+	    dynamic based on a previous setting.  EConfig supports this mode of
+	    operation too, in which case it re-builds the configuration screen
+	    the same way, and automatically destroys the old widgets
+	    <footnote><simpara>In most cases, in some cases additional manual
+		processing is required in the factory
+		callback.</simpara></footnote> and even re-orders pages and
+	    sections where appropriate to make the user-interface consistent.
+	  </para>
+	  <para>
+	    The following few examples some of the flexibility of the EConfig
+	    system.
+	  </para>
+	  <figure id="e-config-build-1">
+	    <title>The application defined, unaltered configuration page.</title>
+	    <mediaobject>
+	      <!-- do we need to build our own eps for the image? -->
+	      <imageobject>
+		<imagedata fileref="images/e-config-build-1.png" format="PNG"/>
+	      </imageobject>
+	      <textobject>
+		<phrase>Shows the original HTML Mail settings page.</phrase>
+	      </textobject>
+	    </mediaobject>
+	  </figure>
+	  <para>
+	    First we have the original configuration window.  This is defined
+	    by the application, the application uses EConfig to build this
+	    window, and in the process EConfig instruments the sections that
+	    the application defines.  This allows plugins to add new
+	    pages/sections/items anywhere on the page - to a granularity as
+	    defined by the application.  For example the application may at
+	    minimum merely define the top-level notebook or druid object and a
+	    number of pages.  When the pages are created the application could
+	    add as much content as it wants, which would still allow plugins to
+	    extend the user interface, but only by adding options to the end of
+	    each page.  At the other end of the scale the application could
+	    enumerate every single item (i.e. row) in every section on every
+	    page, allowing plugins to put new items anywhere in the display.
+	  </para>
+	  <figure id="e-config-build-2">
+	    <title>A plugin adding a new section to an existing page.</title>
+	    <mediaobject>
+	      <!-- do we need to build our own eps for the image? -->
+	      <imageobject>
+		<imagedata fileref="images/e-config-build-2.png" format="PNG"/>
+	      </imageobject>
+	      <textobject>
+		<phrase>Shows the HTML Mail settings page with a new section
+		  and item added by a plugin.</phrase>
+	      </textobject>
+	    </mediaobject>
+	  </figure>
+	  <para>
+	    In this case the plugin has merely added a new section on the
+	    bottom of the HTML Mail settings page.  When the factory is called
+	    the plugin has a parent GtkTable (in this case, it could be a VBox)
+	    and borderless frame already defined, and it just has to
+	    instantiate its own control widgets, add them to the table, and
+	    return one of the widgets.  The returned widget is used later if
+	    the window needs to be reconfigured, although this particular configuration
+	    page is static so it isn't needed.
+	  </para>
+	  <figure id="e-config-build-3">
+	    <title>A plugin inserting a new page for its settings.</title>
+	    <mediaobject>
+	      <!-- do we need to build our own eps for the image? -->
+	      <imageobject>
+		<imagedata fileref="images/e-config-build-3.png" format="PNG"/>
+	      </imageobject>
+	      <textobject>
+		<phrase>Shows the plugin adding a new page for its setting as
+		  an alternative.</phrase>
+	      </textobject>
+	    </mediaobject>
+	  </figure>
+	  <para>
+	    And finally we have exactly the same plugin, which has exactly the
+	    same code.  But a small change to the plugin definition allows the
+	    plugin to add an arbitrary new page (in an arbitrary position) into
+	    the whole window.  If this was a druid, then new druid pages can
+	    also be inserted at arbitrary locations, and page navigation (in a
+	    strictly linear manner) is automatically controlled by EConfig as
+	    per <xref linkend="e-config-flow"/>.
+	  </para>
+	  <para>
+	    In practice, EConfig provides more than it takes the application to
+	    use - generally little or no extra application code is required to
+	    use it.  It also
+	    <footnote><simpara>Or it will - the code needs some
+		tweaking.</simpara></footnote> enforces and simplifies HIG
+	    compliance.  And as a side-benefit to the application it
+	    transparently provides extension hooks for
+	    external code to provide a seamlessly integrated user experience.
+	  </para>
+	</sect2>
+      </sect1>
+
+      <sect1 id="plugin-hooks-event">
+	<title>
+	  Events
+	</title>
+	<para>
+	  No extensibility framework would be complete without an event
+	  system. Events are used to reflect changes in internal state of the
+	  application, and track actions by the user. They can contain any
+	  information and additionally can be filtered based on the information
+	  itself. Special targets are used, as in the other plugin hooks, to
+	  hold this information.
+	</para>
+	<para>
+	  Event managers are defined to contain the different event types that
+	  a given component can export. Only one event manager object is
+	  instantiated for each component, and each plugin listening to events
+	  from that component are registered on that event manager directly.
+	</para>
+	<para>
+	  Events handlers have priorities, and can swallow events, allowing
+	  some level of complexity of event routing. This feature might not
+	  prove useful and may be removed in the future if it isn't.
+	</para>
+	<sect2>
+	  <title>Defining an event hook</title>
+	  <para>
+	    Not sure if this fits here as such.  Probably temporary placeholder.
+	  </para>
+
+	  <programlisting>
+	    <![CDATA[
+<hook class="com.ximian.evolution.mail.events:1.0">
+ <event
+   type="pass | sink"
+   priority="signed integer"
+   id="event name"
+   enable="target mask" ?
+   handle="function spec"/> *
+ </event> *
+</hook>]]></programlisting>
+	  <variablelist>
+	    <varlistentry>
+	      <term><parameter>type</parameter></term>
+	      <listitem>
+		<simpara>
+		  The event listener type.  The type maps directly to the corresponding
+		  corresponding EEventItem types.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>priority</parameter></term>
+	      <listitem>
+		<simpara>
+		  A signed integer specifying the priority of this event
+		  listener.  0 (zero) should be used normally, although positive
+		  and negative integers in the range -128 to 127 may aslo be
+		  used.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>id</parameter></term>
+	      <listitem>
+		<simpara>
+		  The name of the event to listen to.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>enable</parameter></term>
+	      <listitem>
+		<simpara>
+		  A comma separated list of mask enumeration values used to
+		  qualify when this event listener is invoked.  What values are valid
+		  depend on the event hook class.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>handle</parameter></term>
+	      <listitem>
+		<simpara>
+		  A plugin-type specific function specification.  This
+		  function will be resolved and called when an event is routed to
+		  this listener.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	  </variablelist>
+	</sect2>
+      </sect1>
+
+      <sect1 id="plugin-hooks-format">
+	<title>
+	  Mail Formatter
+	</title>
+	<para>
+	  The mail formatter plugin will invoke plugin code to format any part
+	  of an email based on mime-type. There are several formatters used
+	  internally by the mailer for different contexts, and each can be
+	  hooked into separately, providing extensible mail formatting for
+	  everything from the primary mail display, to printing, to reply
+	  quoting and more. If you are implementing a handler for a given
+	  mime-type, each formatter appropriate for the data-type should be
+	  hooked into, so that it displays properly in all contexts.
+	</para>
+	<para>
+	  Since the management object in this case is the same formatting
+	  object as used by the core mail display engine, a plugin may override
+	  or reimplement complete new functionality seamlessly.
+	</para>
+	<para>
+	  This plugin hook isn't strictly part of the core functionality as it
+	  is provided only by the mail component. It however demonstrates that the
+	  plugin system is extensible itself.
+	</para>
+	<sect2>
+	  <title>Defining a formatter hook</title>
+	  <para>
+	    Not sure if this fits here as such.  Probably temporary placeholder.
+	  </para>
+
+	  <programlisting>
+	    <![CDATA[
+<hook class="com.novell.evolution.mail.format:1.0">
+ <group id="formatter type">
+  <item
+    flags="handler flags"
+    mime_type="major/minor"
+    format="function spec"/> +
+ </group> +
+</hook>]]></programlisting>
+	  <variablelist>
+	    <varlistentry>
+	      <term><parameter>id</parameter></term>
+	      <listitem>
+		<simpara>
+		  The actual formatter this applies to.  e.g. EMFormat for the
+		  base formatter class, EMFormatHTML for HTML output to a
+		  GtkHTML object, etc.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>flags</parameter></term>
+	      <listitem>
+		<simpara>
+		  Flags to define whether this is an attachment or inline
+		  content.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>id</parameter></term>
+	      <listitem>
+		<simpara>
+		  The name of the event to listen to.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>mime_type</parameter></term>
+	      <listitem>
+		<simpara>
+		  The type of object this handler formats.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	    <varlistentry>
+	      <term><parameter>format</parameter></term>
+	      <listitem>
+		<simpara>
+		  A plugin-type specific function specification.  This
+		  function will be invoked to format objects of the specified
+		  <parameter>mime_type</parameter>.
+		</simpara>
+	      </listitem>
+	    </varlistentry>
+	  </variablelist>
+	</sect2>
+
+	<sect2>
+	  <title>The formatting process</title>
+	  <para>
+	    The formatting process is driven by the <link
+	      linkend="API-struct--EMFormat">EMFormat</link> object, although
+	    there are different subclasses of this object used for different
+	    purposes.  These behave quite differently so each must be explained
+	    separately.  There is the basic formatter type which converts a
+	    CamelMimeMessage into a stream of data, and there is a HTML
+	    <link linkend="API-struct--EMFormatHTML">formatter type</link>
+	    which uses a GtkHTML object to parse the content
+	    and may request further information required to complete the
+	    formatting.
+	  </para>
+	  <para>
+	    A basic formatter goes through the following steps:
+	  </para>
+	  <orderedlist>
+	    <listitem>
+	      <simpara>Outputs pre-amble information.  e.g. Flag-For-Followup
+		status.</simpara>
+	    </listitem>
+	    <listitem>
+	      <simpara>Invokes <methodname>format_message</methodname> to begin the message
+		formatting. <methodname>format_message</methodname> displays the message header, then
+		looks up the content object.</simpara>
+	    </listitem>
+	    <listitem>
+	      <simpara>Using the mime-type of the content object (whether
+		supplied or calculated), a handler is looked up from a
+		per-class table to process the type.</simpara>
+	    </listitem>
+	    <listitem>
+	      <simpara>If no handler exists, then the data is formatted as an
+		attachment.</simpara>
+	    </listitem>
+	    <listitem>
+	      <simpara>If a handler exists, then it is invoked to display that
+		type.  Depending on whether the data is to be displayed
+		'inline' or not, the data may also get an attachment expander
+		and button.</simpara>
+	    </listitem>
+	    <listitem>
+	      <simpara>The handler transforms the part's data, if need be, and
+		writes the appropriate format output to a stream.</simpara>
+	    </listitem>
+	  </orderedlist>
+	  <para>
+	    For conglomerate types, the formatting process is continued
+	    recursively, until all parts have been displayed, as appropriate.
+	  </para>
+	  <para>
+	    A HTML formatter goes through the same basic steps, but has
+	    additional features and requirements.  It uses multiple
+	    threads.  At least one other thread is used for all of the
+	    Camel message content operations since some of them may block on
+	    remote I/O.  This also simplifies cancellation processing.  Also,
+	    because it has access to a full HTML rendering object, references
+	    to embedded content (images, buttons, etc.) are also processed.
+	  </para>
+	  <para>
+	    Most format handlers don't need to know about all the fiddly
+	    details however.  If they are just outputting HTML content with no
+	    out of band references, they work identical to the basic format
+	    handlers with the exception they cannot call any Gtk GUI code
+	    because of threading issues.  This can still be done by using an
+	    IFRAME.  If they want to embed an icon or other image,
+	    they simply need to insert the HTML IMG tag reference in their
+	    format handler, and setup a callback to handle it when GtkHTML
+	    requests it.  EMFormat has some helper classes to make this
+	    only a few lines of code, including generation of the IMG SRC URL.
+	    IFRAMEs work identically to IMG tags, and  similar process is
+	    involved with embedding custom widgets using the OBJECT tag.
+	    EMFormatHTML takes care of calling the right callbacks for the
+	    right embedded reference from the right thread.
+	  </para>
+	  <para>
+	    Since format handlers are chained off a given type, then a plugin
+	    can also inherit formatting behaviour as well as override it.  This
+	    gives much greater flexibility since the plugin need only implement
+	    its behaviour in specific situations.  e.g. an OpenPGP message
+	    handler could fall-back to the normal text-formatter if it doesn't
+	    detect the ASCII armour in a text/plain part.  Or another handler
+	    may disable itself based on configuration or state.
+	  </para>
+	  <para>
+	    All format handlers for all types must also be fully re-entrant
+	    code (more or less write-once global and static variables) if
+	    they call any other formatting functions.
+	  </para>
+	</sect2>
+      </sect1>
+    </chapter>
+  </part>
+
+  <part>
+    <title>
+      &Evolution; Hook Points.
+    </title>
+    <partintro>
+      <para>
+	This section enumerates all of the published hook points and target
+	types available in each component in &Evolution;.
+      </para>
+
+      <simplesect>
+	<title>Table Format</title>
+	<informaltable>
+	  <tgroup cols="2">
+	    <colspec colnum="1" colname="field" colwidth="1*"/>
+	    <colspec colnum="2" colname="value" colwidth="4*"/>
+	    <tbody>
+	      <row>
+		<entry>Name</entry>
+		<entry>The hook point id.</entry>
+	      </row>
+	      <row>
+		<entry>Target</entry>
+		<entry>The target which this hook uses for its context data.
+		  Targets are described in a following section.
+		</entry>
+	      </row>
+	      <row>
+		<entry>Items</entry>
+		<entry>If appropriate and defined, specifies identifying path
+		  names of items which make up the hook.  e.g. popup menu
+		  items, and configuration pages.  These item specifications
+		  allow the plugin writer to position their items
+		  appropriately.
+		</entry>
+	      </row>
+	    </tbody>
+	  </tgroup>
+	</informaltable>
+      </simplesect>
+
+    </partintro>
+    <chapter id="mail-hooks">
+      <title>
+	Mail Hooks
+      </title>
+      <para>
+	<emphasis>
+	  Need to find out the right docbook to mark-up most of this
+	  text.
+	</emphasis>
+      </para>
+
+      <sect1 id="mail-hooks-popup">
+	<title>Popup menus</title>
+
+	<para>
+	  The mail popup menu class is
+	  <interfacename>com.ximian.evolution.mail.popup:1.0</interfacename>.
+	</para>
+	<para>
+	  The plugin callback data will be the target matching the plugin
+	  menu itself, and the callback returns no value.
+	</para>
+
+	<sect2>
+	  <title>Folder Tree Context Menu</title>
+	  <para>
+	    This is the context menu shown on the folder tree.
+	  </para>
+	  <informaltable>
+	    <tgroup cols="2">
+	      <colspec colnum="1" colname="field" colwidth="1*"/>
+	      <colspec colnum="2" colname="value" colwidth="4*"/>
+	      <tbody valign="top">
+		<row>
+		  <entry>Name</entry>
+		  <entry><interfacename>com.ximian.mail.storageset.popup.select</interfacename></entry>
+		</row>
+		<row>
+		  <entry>Target</entry>
+		  <entry>
+		    <link
+		      linkend="mail-hooks-popup-EMPopupTargetFolder">EMPopupTargetFolder</link>
+		  </entry>
+		</row>
+	      </tbody>
+	    </tgroup>
+	  </informaltable>
+	</sect2>
+
+	<sect2>
+	  <title>Message List Context Menu</title>
+	  <para>
+	    This is the context menu shown on the message list.
+	  </para>
+	  <informaltable>
+	    <tgroup cols="2">
+	      <colspec colnum="1" colname="field" colwidth="1*"/>
+	      <colspec colnum="2" colname="value" colwidth="4*"/>
+	      <tbody valign="top">
+		<row>
+		  <entry>Name</entry>
+		  <entry><interfacename>com.ximian.mail.folderview.popup.select</interfacename></entry>
+		</row>
+		<row>
+		  <entry>Target</entry>
+		  <entry>
+		    <link
+		      linkend="mail-hooks-popup-EMPopupTargetSelect">EMPopupTargetSelect</link>
+		  </entry>
+		</row>
+	      </tbody>
+	    </tgroup>
+	  </informaltable>
+	</sect2>
+
+	<sect2>
+	  <title>Inline URI Context Menu</title>
+	  <para>
+	    This is the context menu shown when clicking on inline URIs,
+	    including addresses or normal HTML links that are displayed inside
+	    the message view.
+	  </para>
+	  <informaltable>
+	    <tgroup cols="2">
+	      <colspec colnum="1" colname="field" colwidth="1*"/>
+	      <colspec colnum="2" colname="value" colwidth="4*"/>
+	      <tbody valign="top">
+		<row>
+		  <entry>Name</entry>
+		  <entry><interfacename>com.ximian.mail.folderview.popup.uri</interfacename></entry>
+		</row>
+		<row>
+		  <entry>Target</entry>
+		  <entry><link
+		      linkend="mail-hooks-popup-EMPopupTargetURI">EMPopupTargetURI</link></entry>
+		</row>
+	      </tbody>
+	    </tgroup>
+	  </informaltable>
+	</sect2>
+
+	<sect2>
+	  <title>Inline Content and Attachment Context Menu</title>
+	  <para>
+	    This context menu is shown when right-clicking on inline images, or
+	    when clicking on the attachment expander button.
+	  </para>
+	  <informaltable>
+	    <tgroup cols="2">
+	      <colspec colnum="1" colname="field" colwidth="1*"/>
+	      <colspec colnum="2" colname="value" colwidth="4*"/>
+	      <tbody valign="top">
+		<row>
+		  <entry>Name</entry>
+		  <entry><interfacename>com.ximian.mail.formathtmldisplay.popup.part</interfacename></entry>
+		</row>
+		<row>
+		  <entry>Target</entry>
+		  <entry><link
+		      linkend="mail-hooks-popup-EMPopupTargetPart">EMPopupTargetPart</link></entry>
+		</row>
+	      </tbody>
+	    </tgroup>
+	  </informaltable>
+	</sect2>
+
+	<sect2>
+	  <title>Composer Attachment Bar Context Menu</title>
+	  <para>
+	    This context menu is displayed when the user brings up a context
+	    menu on the attachment bar displayed in the composer.
+	  </para>
+	  <informaltable>
+	    <tgroup cols="2">
+	      <colspec colnum="1" colname="field" colwidth="1*"/>
+	      <colspec colnum="2" colname="value" colwidth="4*"/>
+	      <tbody valign="top">
+		<row>
+		  <entry>Name</entry>
+		  <entry><interfacename>com.novell.evolution.mail.composer.attachmentBar</interfacename></entry>
+		</row>
+		<row>
+		  <entry>Target</entry>
+		  <entry><link
+		      linkend="mail-hooks-popup-EMPopupTargetAttachments">EMPopupTargetAttachments</link></entry>
+		</row>
+		<row>
+		  <entry>Qualifiers</entry>
+		  <entry>
+		    <simplelist>
+		      <member><constant>one</constant> = <constant>EM_POPUP_ATTACHMENTS_ONE</constant></member>
+		      <member><constant>many</constant> = <constant>EM_POPUP_ATTACHMENTS_MANY</constant></member>
+		    </simplelist>
+		  </entry>
+		</row>
+	      </tbody>
+	    </tgroup>
+	  </informaltable>
+	</sect2>
+
+	<sect2>
+	  <title>Internal popup menus</title>
+	  <para>
+	    The following popup menus are defined, but they are used with no
+	    target, and so provide no useful context if they were to be hooked
+	    onto.
+	  </para>
+	  <para>
+	    <interfacename>com.ximian.mail.messagelist.popup.drop</interfacename>
+	    is used for the ASK drop type on the message list.
+	  </para>
+	  <para>
+	    <interfacename>com.ximian.mail.storageset.popup.drop</interfacename>
+	    is used for the ASK drop type on the folder tree.
+	  </para>
+	</sect2>
+
+	<sect2>
+	  <title>Mail Popup Targets</title>
+
+	  <para>
+	    <emphasis>
+	      Not sure if this needs to explain the qualifier meanings, or
+	      leave it to the in-line comment stuff in the enumeration
+	      definition.  Maybe it just needs a direct link to the
+	      enumeration.
+	    </emphasis>
+	  </para>
+
+	  <sect3 id="mail-hooks-popup-EMPopupTargetFolder">
+	    <title>Folder Target</title>
+
+	    <para>
+	      This target is used to define actions on a folder context.
+	      Normally associated with the folder tree.
+	    </para>
+
+	    <informaltable>
+	      <tgroup cols="2">
+		<colspec colnum="1" colname="field" colwidth="1*"/>
+		<colspec colnum="2" colname="value" colwidth="4*"/>
+		<tbody valign="top">
+		  <row>
+		    <entry>Name</entry>
+		    <entry><constant>folder</constant></entry>
+		  </row>
+		  <row>
+		    <entry>Structure</entry>
+		    <entry>
+		      <link
+			linkend="API-struct--EMPopupTargetFolder">EMPopupTargetFolder</link>
+		    </entry>
+		  </row>
+		  <row>
+		    <entry>Qualifiers</entry>
+		    <entry>
+		      <simplelist>
+			<member><constant>folder</constant> = <constant>EM_POPUP_FOLDER_FOLDER</constant></member>
+			<member><constant>store</constant> = <constant>EM_POPUP_FOLDER_STORE</constant></member>
+			<member><constant>inferiors</constant> = <constant>EM_POPUP_FOLDER_INFERIORS</constant></member>
+			<member><constant>delete</constant> = <constant>EM_POPUP_FOLDER_DELETE</constant></member>
+			<member><constant>select</constant> = <constant>EM_POPUP_FOLDER_SELECT</constant></member>
+		      </simplelist>
+		    </entry>
+		  </row>
+		</tbody>
+	      </tgroup>
+	    </informaltable>
+	  </sect3>
+
+	  <sect3 id="mail-hooks-popup-EMPopupTargetSelect">
+	    <title>Selection Target</title>
+
+	    <para>This target is used to define context for actions associated
+	      with a selection of mail messages from a specific folder.</para>
+
+	    <informaltable>
+	      <tgroup cols="2">
+		<colspec colnum="1" colname="field" colwidth="1*"/>
+		<colspec colnum="2" colname="value" colwidth="4*"/>
+		<tbody valign="top">
+		  <row>
+		    <entry>Name</entry>
+		    <entry><constant>select</constant></entry>
+		  </row>
+		  <row>
+		    <entry>Structure</entry>
+		    <entry>
+		      <link
+			linkend="API-struct--EMPopupTargetSelect">EMPopupTargetSelect</link>
+		    </entry>
+		  </row>
+		  <row>
+		    <entry>Qualifiers</entry>
+		    <entry>
+		      <simplelist>
+			<member><constant>one</constant> = <constant>EM_POPUP_SELECT_ONE</constant></member>
+			<member><constant>many</constant> = <constant>EM_POPUP_SELECT_MANY</constant></member>
+			<member><constant>mark_read</constant> = <constant>EM_POPUP_SELECT_MARK_READ</constant></member>
+			<member><constant>mark_unread</constant> = <constant>EM_POPUP_SELECT_MARK_UNREAD</constant></member>
+			<member><constant>delete</constant> = <constant>EM_POPUP_SELECT_DELETE</constant></member>
+			<member><constant>undelete</constant> = <constant>EM_POPUP_SELECT_UNDELETE</constant></member>
+			<member><constant>mailing_list</constant> = <constant>EM_POPUP_SELECT_MAILING_LIST</constant></member>
+			<member><constant>resend</constant> = <constant>EM_POPUP_SELECT_EDIT</constant></member>
+			<member><constant>mark_important</constant> = <constant>EM_POPUP_SELECT_MARK_IMPORTANT</constant></member>
+			<member><constant>mark_unimportant</constant> = <constant>EM_POPUP_SELECT_MARK_UNIMPORTANT</constant></member>
+			<member><constant>flag_followup</constant> = <constant>EM_POPUP_SELECT_FLAG_FOLLOWUP</constant></member>
+			<member><constant>flag_completed</constant> = <constant>EM_POPUP_SELECT_FLAG_COMPLETED</constant></member>
+			<member><constant>flag_clear</constant> = <constant>EM_POPUP_SELECT_FLAG_CLEAR</constant></member>
+			<member><constant>add_sender</constant> = <constant>EM_POPUP_SELECT_ADD_SENDER</constant></member>
+			<member><constant>mark_junk</constant> = <constant>EM_POPUP_SELECT_MARK_JUNK</constant></member>
+			<member><constant>mark_nojunk</constant> = <constant>EM_POPUP_SELECT_MARK_NOJUNK</constant></member>
+			<member><constant>folder</constant> = <constant>EM_POPUP_SELECT_FOLDER</constant></member>
+		      </simplelist>
+		    </entry>
+		  </row>
+		</tbody>
+	      </tgroup>
+	    </informaltable>
+	  </sect3>
+
+	  <sect3 id="mail-hooks-popup-EMPopupTargetURI">
+	    <title>URI Target</title>
+
+	    <para>This target defines context for operations on a URI, normally
+	      displayed inline somewhere in the message view.</para>
+
+	    <informaltable>
+	      <tgroup cols="2">
+		<colspec colnum="1" colname="field" colwidth="1*"/>
+		<colspec colnum="2" colname="value" colwidth="4*"/>
+		<tbody valign="top">
+		  <row>
+		    <entry>Name</entry>
+		    <entry><constant>uri</constant></entry>
+		  </row>
+		  <row>
+		    <entry>Structure</entry>
+		    <entry><link
+			linkend="API-struct--EMPopupTargetURI">EMPopupTargetURI</link></entry>
+		  </row>
+		  <row>
+		    <entry>Qualifiers</entry>
+		    <entry>
+		      <simplelist>
+			<member><constant>http</constant> = <constant>EM_POPUP_URI_HTTP</constant></member>
+			<member><constant>mailto</constant> = <constant>EM_POPUP_URI_MAILTO</constant></member>
+			<member><constant>notmailto</constant> = <constant>EM_POPUP_URI_NOT_MAILTO</constant></member>
+		      </simplelist>
+		    </entry>
+		  </row>
+		</tbody>
+	      </tgroup>
+	    </informaltable>
+	  </sect3>
+
+	  <sect3 id="mail-hooks-popup-EMPopupTargetPart">
+	    <title>Message Part Target</title>
+
+	    <para>This target defines context for operations on messages, or
+	      individual message parts.  The same target is used for inline
+	      images or other content which can be encapsulated in a MIME part
+	      (i.e. anything).</para>
+
+	    <informaltable>
+	      <tgroup cols="2">
+		<colspec colnum="1" colname="field" colwidth="1*"/>
+		<colspec colnum="2" colname="value" colwidth="4*"/>
+		<tbody valign="top">
+		  <row>
+		    <entry>Name</entry>
+		    <entry><constant>part</constant></entry>
+		  </row>
+		  <row>
+		    <entry>Structure</entry>
+		    <entry><link
+			linkend="API-struct--EMPopupTargetPart">EMPopupTargetPart</link></entry>
+		  </row>
+		  <row>
+		    <entry>Qualifiers</entry>
+		    <entry>
+		      <simplelist>
+			<member><constant>message</constant> = <constant>EM_POPUP_PART_MESSAGE</constant></member>
+			<member><constant>image</constant> = <constant>EM_POPUP_PART_IMAGE</constant></member>
+		      </simplelist>
+		    </entry>
+		  </row>
+		</tbody>
+	      </tgroup>
+	    </informaltable>
+	  </sect3>
+
+	  <sect3 id="mail-hooks-popup-EMPopupTargetAttachments">
+	    <title>Attachments Target</title>
+
+	    <para>This target is used to define context for operations on the
+	      mail composer attachment bar.</para>
+
+	    <informaltable>
+	      <tgroup cols="2">
+		<colspec colnum="1" colname="field" colwidth="1*"/>
+		<colspec colnum="2" colname="value" colwidth="4*"/>
+		<tbody valign="top">
+		  <row>
+		    <entry>Name</entry>
+		    <entry><constant>attachments</constant></entry>
+		  </row>
+		  <row>
+		    <entry>Structure</entry>
+		    <entry><link
+			linkend="API-struct--EMPopupTargetAttachments">EMPopupTargetAttachments</link></entry>
+		  </row>
+		  <row>
+		    <entry>Qualifiers</entry>
+		    <entry>
+		      <simplelist>
+			<member><constant>one</constant> = <constant>EM_POPUP_ATTACHMENTS_ONE</constant></member>
+			<member><constant>many</constant> = <constant>EM_POPUP_ATTACHMENTS_MANY</constant></member>
+		      </simplelist>
+		    </entry>
+		  </row>
+		</tbody>
+	      </tgroup>
+	    </informaltable>
+	  </sect3>
+
+	</sect2>
+      </sect1>
+
+      <sect1 id="mail-hooks-menu">
+	<title>Main menus</title>
+
+	<para>
+	  The mail popup menu class is
+	  <interfacename>com.ximian.evolution.mail.bonobomenu:1.0</interfacename>.
+	</para>
+	<para>
+	  The plugin callback data will be the target matching the plugin
+	  menu itself, and the callback returns no value.
+	</para>
+
+	<sect2>
+	  <title>Main Mail Menu</title>
+
+	  <para>
+	    This is the main mail view embedded in the &Evolution; Shell.
+	  </para>
+
+	  <informaltable>
+	    <tgroup cols="2">
+	      <colspec colnum="1" colname="field" colwidth="1*"/>
+	      <colspec colnum="2" colname="value" colwidth="4*"/>
+	      <tbody valign="top">
+		<row>
+		  <entry>Name</entry>
+		  <entry><interfacename>com.novell.evolution.mail.browser</interfacename></entry>
+		</row>
+		<row>
+		  <entry>Target</entry>
+		  <entry>
+		    <link
+		      linkend="mail-hooks-menu-EMMenuTargetSelect">EMMenuTargetSelect</link>
+		  </entry>
+		</row>
+	      </tbody>
+	    </tgroup>
+	  </informaltable>
+	</sect2>
+
+	<sect2>
+	  <title>Standalone Message View Menu</title>
+
+	  <para>
+	    This is the popup mail-message view.
+	  </para>
+
+	  <informaltable>
+	    <tgroup cols="2">
+	      <colspec colnum="1" colname="field" colwidth="1*"/>
+	      <colspec colnum="2" colname="value" colwidth="4*"/>
+	      <tbody valign="top">
+		<row>
+		  <entry>Name</entry>
+		  <entry><interfacename>com.novell.evolution.mail.messagebrowser</interfacename></entry>
+		</row>
+		<row>
+		  <entry>Target</entry>
+		  <entry>
+		    <link
+		      linkend="mail-hooks-menu-EMMenuTargetSelect">EMMenuTargetSelect</link>,
+		  </entry>
+		</row>
+	      </tbody>
+	    </tgroup>
+	  </informaltable>
+	</sect2>
+
+	<sect2>
+	  <title>Composer Menu</title>
+	  <para>
+	    This is the mail message composer.  This is currently not implemented.
+	  </para>
+	  <informaltable>
+	    <tgroup cols="2">
+	      <colspec colnum="1" colname="field" colwidth="1*"/>
+	      <colspec colnum="2" colname="value" colwidth="4*"/>
+	      <tbody valign="top">
+		<row>
+		  <entry>Name</entry>
+		  <entry><interfacename>com.novell.evolution.mail.composer</interfacename></entry>
+		</row>
+		<row>
+		  <entry>Target</entry>
+		  <entry>Undefined</entry>
+		</row>
+		<row>
+		  <entry>Qualifiers</entry>
+		  <entry>Undefined</entry>
+		</row>
+	      </tbody>
+	    </tgroup>
+	  </informaltable>
+	</sect2>
+
+	<sect2>
+	  <title>Mail Menu Targets</title>
+
+	  <sect3 id="mail-hooks-menu-EMMenuTargetSelect">
+	    <title>Message Selection Target</title>
+
+	    <para>This target is used to define context for operations on a
+	      selection of messages in the view's message list.</para>
+
+	    <informaltable>
+	      <tgroup cols="2">
+		<colspec colnum="1" colname="field" colwidth="1*"/>
+		<colspec colnum="2" colname="value" colwidth="4*"/>
+		<tbody valign="top">
+		  <row>
+		    <entry>Name</entry>
+		    <entry><constant>select</constant></entry>
+		  </row>
+		  <row>
+		    <entry>Structure</entry>
+		    <entry>
+		      <link
+			linkend="API-struct--EMMenuTargeSelect">EMMenuTargetSelect</link>
+		    </entry>
+		  </row>
+		  <row>
+		    <entry>Qualifiers</entry>
+		    <entry>
+		      <simplelist>
+			<member><constant>one</constant> = <constant>EM_MENU_SELECT_ONE</constant></member>
+			<member><constant>many</constant> = <constant>EM_MENU_SELECT_MANY</constant></member>
+			<member><constant>mark_read</constant> = <constant>EM_MENU_SELECT_MARK_READ</constant></member>
+			<member><constant>mark_unread</constant> = <constant>EM_MENU_SELECT_MARK_UNREAD</constant></member>
+			<member><constant>delete</constant> = <constant>EM_MENU_SELECT_DELETE</constant></member>
+			<member><constant>undelete</constant> = <constant>EM_MENU_SELECT_UNDELETE</constant></member>
+			<member><constant>mailing_list</constant> = <constant>EM_MENU_SELECT_MAILING_LIST</constant></member>
+			<member><constant>resend</constant> = <constant>EM_MENU_SELECT_EDIT</constant></member>
+			<member><constant>mark_important</constant> = <constant>EM_MENU_SELECT_MARK_IMPORTANT</constant></member>
+			<member><constant>mark_unimportant</constant> = <constant>EM_MENU_SELECT_MARK_UNIMPORTANT</constant></member>
+			<member><constant>flag_followup</constant> = <constant>EM_MENU_SELECT_FLAG_FOLLOWUP</constant></member>
+			<member><constant>flag_completed</constant> = <constant>EM_MENU_SELECT_FLAG_COMPLETED</constant></member>
+			<member><constant>flag_clear</constant> = <constant>EM_MENU_SELECT_FLAG_CLEAR</constant></member>
+			<member><constant>add_sender</constant> = <constant>EM_MENU_SELECT_ADD_SENDER</constant></member>
+			<member><constant>mark_junk</constant> = <constant>EM_MENU_SELECT_MARK_JUNK</constant></member>
+			<member><constant>mark_nojunk</constant> = <constant>EM_MENU_SELECT_MARK_NOJUNK</constant></member>
+			<member><constant>folder</constant> = <constant>EM_MENU_SELECT_FOLDER</constant></member>
+		      </simplelist>
+		    </entry>
+		  </row>
+		</tbody>
+	      </tgroup>
+	    </informaltable>
+	  </sect3>
+	</sect2>
+      </sect1>
+
+      <sect1 id="mail-hooks-config">
+	<title>Config Windows and Druids</title>
+
+	<para>
+	  The mail config class is
+	  <interfacename>com.novell.evolution.mail.config:1.0</interfacename>.
+	</para>
+
+	<sect2>
+	  <title>Account Editor Druid</title>
+	  <para>
+	    This is the GnomeDruid which is shown when you create a new mail account.
+	  </para>
+	  <informaltable>
+	    <tgroup cols="2">
+	      <colspec colnum="1" colname="field" colwidth="1*"/>
+	      <colspec colnum="2" colname="value" colwidth="4*"/>
+	      <tbody valign="top">
+		<row>
+		  <entry>Name</entry>
+		  <entry><interfacename>com.novell.evolution.mail.config.accountDruid</interfacename></entry>
+		</row>
+		<row>
+		  <entry>Target</entry>
+		  <entry>
+		    <link
+		      linkend="mail-hooks-config-EMConfigTargetAccount">EMConfigTargetAccount</link>
+		  </entry>
+		</row>
+		<row>
+		  <entry>Items</entry>
+		  <entry>Define some of the items available and where they fit
+		    in the gui</entry>
+		</row>
+	      </tbody>
+	    </tgroup>
+	  </informaltable>
+	</sect2>
+
+	<sect2>
+	  <title>Account Editor Window</title>
+	  <para>
+	    This is the editor notebook which is shown when you edit an
+	    existing mail account.
+	  </para>
+	  <informaltable>
+	    <tgroup cols="2">
+	      <colspec colnum="1" colname="field" colwidth="1*"/>
+	      <colspec colnum="2" colname="value" colwidth="4*"/>
+	      <tbody valign="top">
+		<row>
+		  <entry>Name</entry>
+		  <entry><interfacename>com.novell.evolution.mail.config.accountEditor</interfacename></entry>
+		</row>
+		<row>
+		  <entry>Target</entry>
+		  <entry>
+		    <link
+		      linkend="API-struct--EMConfigTargetAccount">EMConfigTargetAccount</link>, plugin target is &quot;<constant>account</constant>&quot;.
+		  </entry>
+		</row>
+		<row>
+		  <entry>Items</entry>
+		  <entry>Define some of the items available and where they fit
+		    in the gui</entry>
+		</row>
+	      </tbody>
+	    </tgroup>
+	  </informaltable>
+	</sect2>
+
+	<sect2>
+	  <title>Composer Preferences</title>
+	  <para>
+	    This is the notebook of configuration items for the composer which
+	    are accessed via the main settings window under the Composer tab.
+	  </para>
+	  <informaltable>
+	    <tgroup cols="2">
+	      <colspec colnum="1" colname="field" colwidth="1*"/>
+	      <colspec colnum="2" colname="value" colwidth="4*"/>
+	      <tbody valign="top">
+		<row>
+		  <entry>Name</entry>
+		  <entry><interfacename>com.novell.evolution.mail.composerPrefs</interfacename></entry>
+		</row>
+		<row>
+		  <entry>Target</entry>
+		  <entry>
+		    <link
+		      linkend="mail-hooks-config-EMConfigTargetPrefs">EMConfigTargetPrefs</link>
+		  </entry>
+		</row>
+		<row>
+		  <entry>Items</entry>
+		  <entry>Define some of the items available and where they fit
+		    in the gui</entry>
+		</row>
+	      </tbody>
+	    </tgroup>
+	  </informaltable>
+	</sect2>
+
+	<sect2>
+	  <title>Mail Preferences</title>
+	  <para>
+	    This is the notebook of configuration items for the mailer which
+	    are accessed via the main settings window under the Mail Settings tab.
+	  </para>
+	  <informaltable>
+	    <tgroup cols="2">
+	      <colspec colnum="1" colname="field" colwidth="1*"/>
+	      <colspec colnum="2" colname="value" colwidth="4*"/>
+	      <tbody valign="top">
+		<row>
+		  <entry>Name</entry>
+		  <entry><interfacename>com.novell.evolution.mail.prefs</interfacename></entry>
+		</row>
+		<row>
+		  <entry>Target</entry>
+		  <entry>
+		    <link
+		      linkend="mail-hooks-config-EMConfigTargetPrefs">EMConfigTargetPrefs</link>
+		  </entry>
+		</row>
+		<row>
+		  <entry>Items</entry>
+		  <entry>Define some of the items available and where they fit
+		    in the gui</entry>
+		</row>
+	      </tbody>
+	    </tgroup>
+	  </informaltable>
+	</sect2>
+
+	<sect2>
+	  <title>Folder Properties</title>
+	  <para>
+	    This is the notebook of configuration items for a given mail folder
+	    which is accessed via the Folder Properties item in the main menu item or
+	    folder-tree context menu.
+	  </para>
+	  <informaltable>
+	    <tgroup cols="2">
+	      <colspec colnum="1" colname="field" colwidth="1*"/>
+	      <colspec colnum="2" colname="value" colwidth="4*"/>
+	      <tbody valign="top">
+		<row>
+		  <entry>Name</entry>
+		  <entry><interfacename>com.novell.evolution.mail.folderConfig</interfacename></entry>
+		</row>
+		<row>
+		  <entry>Target</entry>
+		  <entry>
+		    <link
+		      linkend="mail-hooks-config-EMConfigTargetFolder">EMConfigTargetFolder</link>
+		  </entry>
+		</row>
+		<row>
+		  <entry>Items</entry>
+		  <entry>Define some of the items available and where they fit
+		    in the gui</entry>
+		</row>
+	      </tbody>
+	    </tgroup>
+	  </informaltable>
+	</sect2>
+
+	<sect2>
+	  <title>Mail Config Targets</title>
+
+	  <sect3 id="mail-hooks-config-EMConfigTargetAccount">
+	    <title>Account Target</title>
+
+	    <para>The account target is used for configuring accounts, and so
+	      has a pointer to the EAccount being configured.  This is a copy
+	      of the actual account object, and is copied to the original once
+	      the data is ready to commit.</para>
+
+	    <informaltable>
+	      <tgroup cols="2">
+		<colspec colnum="1" colname="field" colwidth="1*"/>
+		<colspec colnum="2" colname="value" colwidth="4*"/>
+		<tbody valign="top">
+		  <row>
+		    <entry>Name</entry>
+		    <entry><constant>account</constant></entry>
+		  </row>
+		  <row>
+		    <entry>Structure</entry>
+		    <entry>
+		      <link
+			linkend="API-struct--EMConfigTargetAccount">EMConfigTargetAccount</link>
+		    </entry>
+		  </row>
+		  <row>
+		    <entry>Items</entry>
+		    <entry>Define some of the items available and where they fit
+		      in the gui</entry>
+		  </row>
+		</tbody>
+	      </tgroup>
+	    </informaltable>
+	  </sect3>
+
+	  <sect3 id="mail-hooks-config-EMConfigTargetPrefs">
+	    <title>Preferences Target</title>
+
+	    <para>The preferences target is used for global preferences.  As
+	      such it just contains a pointer to the global configuration store
+	      - a GConfClient.</para>
+	    
+	    <informaltable>
+	      <tgroup cols="2">
+		<colspec colnum="1" colname="field" colwidth="1*"/>
+		<colspec colnum="2" colname="value" colwidth="4*"/>
+		<tbody valign="top">
+		  <row>
+		    <entry>Name</entry>
+		    <entry><constant>prefs</constant></entry>
+		  </row>
+		  <row>
+		    <entry>Structure</entry>
+		    <entry>
+		      <link
+			linkend="API-struct--EMConfigTargetPrefs">EMConfigTargetPrefs</link>
+		    </entry>
+		  </row>
+		</tbody>
+	      </tgroup>
+	    </informaltable>
+	  </sect3>
+	  
+	  <sect3 id="mail-hooks-config-EMConfigTargetFolder">
+	    <title>Folder Target</title>
+
+	    <informaltable>
+	      <tgroup cols="2">
+		<colspec colnum="1" colname="field" colwidth="1*"/>
+		<colspec colnum="2" colname="value" colwidth="4*"/>
+		<tbody valign="top">
+		  <row>
+		    <entry>Name</entry>
+		    <entry><constant>folder</constant></entry>
+		  </row>
+		  <row>
+		    <entry>Structure</entry>
+		    <entry>
+		      <link
+			linkend="API-struct--EMConfigTargetFolder">EMConfigTargetFolder</link>
+		    </entry>
+		  </row>
+		</tbody>
+	      </tgroup>
+	    </informaltable>
+	  </sect3>
+	  
+	</sect2>
+      </sect1>
+
+      <sect1 id="mail-hooks-event">
+	<title>Events</title>
+
+	<para>
+	  The mail event class is
+	  <interfacename>com.ximian.evolution.mail.events:1.0</interfacename>.
+	</para>
+
+	<sect2>
+	  <title>Folder Changed Event</title>
+	  <informaltable>
+	    <tgroup cols="2">
+	      <colspec colnum="1" colname="field" colwidth="1*"/>
+	      <colspec colnum="2" colname="value" colwidth="4*"/>
+	      <tbody valign="top">
+		<row>
+		  <entry>Name</entry>
+		  <entry><constant>folder.changed</constant></entry>
+		</row>
+		<row>
+		  <entry>Target</entry>
+		  <entry>
+		    <link
+		      linkend="mail-hooks-event-EMEventTargetFolder">EMEventTargetFolder</link>
+		  </entry>
+		</row>
+	      </tbody>
+	    </tgroup>
+	  </informaltable>
+	</sect2>
+
+	<sect2>
+	  <title>Mail Event Targets</title>
+
+	  <sect3 id="mail-hooks-event-EMEventTargetFolder">
+	    <title>Folder Target</title>
+	    
+	    <informaltable>
+	      <tgroup cols="2">
+		<colspec colnum="1" colname="field" colwidth="1*"/>
+		<colspec colnum="2" colname="value" colwidth="4*"/>
+		<tbody valign="top">
+		  <row>
+		    <entry>Name</entry>
+		    <entry><constant>folder</constant></entry>
+		  </row>
+		  <row>
+		    <entry>Structure</entry>
+		    <entry>
+		      <link
+			linkend="API-struct--EMEventTargetFolder">EMEventTargetFolder</link>
+		    </entry>
+		  </row>
+		  <row>
+		    <entry>Qualifiers</entry>
+		    <entry>List qualifiers</entry>
+		  </row>
+		</tbody>
+	      </tgroup>
+	    </informaltable>
+	  </sect3>
+	</sect2>
+      </sect1>
+
+      <sect1 id="mail-hooks-format">
+	<title>Formatters</title>
+
+	<para>
+	  The mail formatter hook class is
+	  <interfacename>com.novell.evolution.mail.format:1.0</interfacename>.
+	</para>
+
+	<sect2>
+	  <title>Base Formatter</title>
+
+	  <para>
+	    The EMFormat class is the base class for all formatting types.
+	    It should only be used to define compound and complex types which
+	    do not rely on outputting any textual information, or rely on any
+	    screen or print output differences.
+	  </para>
+
+	  <informaltable>
+	    <tgroup cols="2">
+	      <colspec colnum="1" colname="field" colwidth="1*"/>
+	      <colspec colnum="2" colname="value" colwidth="4*"/>
+	      <tbody valign="top">
+		<row>
+		  <entry>Name</entry>
+		  <entry><constant>EMFormat</constant></entry>
+		</row>
+		<row>
+		  <entry>Target</entry>
+		  <entry>
+		    <link
+		      linkend="mail-hooks-format-EMFormatHookTarget">EMFormatHookTarget</link>
+		  </entry>
+		</row>
+	      </tbody>
+	    </tgroup>
+	  </informaltable>
+	</sect2>
+
+	<sect2>
+	  <title>HTML Formatter</title>
+
+	  <para>
+	    The EMFormatHTML class is the base class for most formatting types
+	    which generate HTML output.  It renders output to a GtkHTML
+	    object.  It uses a fairly complex multi-thread approach to the
+	    formatting to ensure the user-interface is not blocked for
+	    processing.  GtkHTML is used in a limited way by this class for
+	    HTML parsing and resolution of embedded objects.  Embedded objects
+	    and Widgets may not be used from formatters which hook onto this
+	    entry point.
+	  </para>
+
+	  <informaltable>
+	    <tgroup cols="2">
+	      <colspec colnum="1" colname="field" colwidth="1*"/>
+	      <colspec colnum="2" colname="value" colwidth="4*"/>
+	      <tbody valign="top">
+		<row>
+		  <entry>Name</entry>
+		  <entry><constant>EMFormatHTML</constant></entry>
+		</row>
+		<row>
+		  <entry>Target</entry>
+		  <entry>
+		    <link
+		      linkend="mail-hooks-format-EMFormatHookTarget">EMFormatHookTarget</link>
+		  </entry>
+		</row>
+	      </tbody>
+	    </tgroup>
+	  </informaltable>
+
+	  <para>
+	    <emphasis>This section needs a huge amount of
+	      explanation, and/or more detail needs to be added to another
+	      section about the formatter class</emphasis>
+	  </para>
+	</sect2>
+
+	<sect2>
+	  <title>HTML Display Formatter</title>
+
+	  <para>
+	    The EMFormatHTMLDisplay class is a subclass of EMFormatHTML, and is
+	    used as a mail display widget.  As such, it has access to all of
+	    the facilities of GtkHTML, such as embedded widgets.  Like the
+	    EMFormatHTML class, this uses a complex multi-thread architecture.
+	  </para>
+
+	  <informaltable>
+	    <tgroup cols="2">
+	      <colspec colnum="1" colname="field" colwidth="1*"/>
+	      <colspec colnum="2" colname="value" colwidth="4*"/>
+	      <tbody valign="top">
+		<row>
+		  <entry>Name</entry>
+		  <entry><constant>EMFormatHTMLDisplay</constant></entry>
+		</row>
+		<row>
+		  <entry>Target</entry>
+		  <entry>
+		    <link
+		      linkend="mail-hooks-format-EMFormatHookTarget">EMFormatHookTarget</link>
+		  </entry>
+		</row>
+	      </tbody>
+	    </tgroup>
+	  </informaltable>
+
+	  <para>
+	    <emphasis>This section needs a huge amount of
+	      explanation, and/or more detail needs to be added to another
+	      section about the formatter class</emphasis>
+	  </para>
+	</sect2>
+
+	<sect2>
+	  <title>HTML Print Formatter</title>
+
+	  <para>
+	    The EMFormatHTMLPrint class is a subclass of EMFormatHTML, and is
+	    used as a mail printing widget.  It cannot access embedded
+	    widgets.  For most purposes you would normally only connect to the
+	    EMFormatHTML hook, and generate generic HTML output which could be
+	    printed or shown on-screen if it isn't overriden by the display
+	    formatter.
+	  </para>
+
+	  <informaltable>
+	    <tgroup cols="2">
+	      <colspec colnum="1" colname="field" colwidth="1*"/>
+	      <colspec colnum="2" colname="value" colwidth="4*"/>
+	      <tbody valign="top">
+		<row>
+		  <entry>Name</entry>
+		  <entry><constant>EMFormatHTMLPrint</constant></entry>
+		</row>
+		<row>
+		  <entry>Target</entry>
+		  <entry>
+		    <link
+		      linkend="mail-hooks-format-EMFormatHookTarget">EMFormatHookTarget</link>
+		  </entry>
+		</row>
+	      </tbody>
+	    </tgroup>
+	  </informaltable>
+
+	  <para>
+	    <emphasis>This section needs a huge amount of
+	      explanation, and/or more detail needs to be added to another
+	      section about the formatter class</emphasis>
+	  </para>
+	</sect2>
+
+	<sect2>
+	  <title>Mail Quote Formatter</title>
+	  <para>
+	    The EMFormatQuote class is a subclass of EMFormat, and is
+	    used as generator for quoted mail content and for
+	    inline-forwarding.  This formatter converts message objects into
+	    a pure HTML stream, which is not parsed directly, but normally fed
+	    to the message composer.
+	  </para>
+	  <informaltable>
+	    <tgroup cols="2">
+	      <colspec colnum="1" colname="field" colwidth="1*"/>
+	      <colspec colnum="2" colname="value" colwidth="4*"/>
+	      <tbody valign="top">
+		<row>
+		  <entry>Name</entry>
+		  <entry><constant>EMFormatQuote</constant></entry>
+		</row>
+		<row>
+		  <entry>Target</entry>
+		  <entry>
+		    <link
+		      linkend="mail-hooks-EMFormatHookTarget">EMFormatHookTarget</link>
+		  </entry>
+		</row>
+	      </tbody>
+	    </tgroup>
+	  </informaltable>
+	</sect2>
+
+	<sect2 id="mail-hooks-format-EMFormatHookTarget">
+	  <title>Mail Formatter Targets</title>
+
+	  <para>There is only one target for all mail formatters, and it is
+	    implied automatically for all formatter hooks.</para>
+
+	  <informaltable>
+	    <tgroup cols="2">
+	      <colspec colnum="1" colname="field" colwidth="1*"/>
+	      <colspec colnum="2" colname="value" colwidth="4*"/>
+	      <tbody valign="top">
+		<row>
+		  <entry>Structure</entry>
+		  <entry>
+		    <link
+		      linkend="API-struct--EMFormatHookTarget">EMFormatHookTarget</link>
+		  </entry>
+		</row>
+		<row>
+		  <entry>Flags</entry>
+		  <entry>
+		    <simplelist>
+		      <member><constant>inline</constant> = <constant>EM_FORMAT_HANDLER_INLINE</constant></member>
+		      <member><constant>inline_disposition</constant> =
+			<constant>EM_FORMAT_HANDLER_INLINE_DISPOSITION</constant></member>
+		      </simplelist>
+		  </entry>
+		</row>
+	      </tbody>
+	    </tgroup>
+	  </informaltable>
+
+	</sect2>
+      </sect1>
+    </chapter>
+
+    <chapter id="contacts-hooks">
+      <title>
+	Contacts Hooks
+      </title>
+      <para>
+	None defined.
+      </para>
+    </chapter>
+
+    <chapter id="calendar-hooks">
+      <title>
+	Calendar and Tasks Hooks
+      </title>
+      <para>
+	None defined.
+      </para>
+    </chapter>
+
+    <chapter id="shell-hooks">
+      <title>
+	Shell Hooks
+      </title>
+      <para>
+	None defined.
+      </para>
+    </chapter>
+
+  </part>
+
+  <part id="reference">
+    <title>
+      Reference
+    </title>
+    <partintro>
+      <para>
+	This section of the book is a detailed API reference of the
+	objects and methods that implement the core plugin system and hooks.
+      </para>
+      <para>
+	It contains the detailed information required for all uses of the
+	plugin system. That is, implementors
+	of new hook types, application developers providing hook points, and
+	plugin developers.
+      </para>
+    </partintro>
+    <chapter id="REF-EPlugin">
+      <title>
+	EPlugin
+      </title>
+      <para>
+	The EPlugin object manages the loading and invocation of physical
+	plugin definitions and plugin binaries.  The base EPlugin class is an
+	abstract class which loads plugin definitons, resolving hooks, and
+	provides an api for invoking callbacks.
+      </para>
+      <para>
+	The EPluginLib object is a concrete derived class of EPlugin which
+	handles loading shared libraries using the GModule interface.
+      </para>
+      &e-plugin-reference;
+    </chapter>
+
+    <chapter>
+      <title>
+	EPopup
+      </title>
+      <para>
+	The EPopup object manages a single popup menu.  It is used to
+	application code as a convenience function for building dynamic popup
+	menus based on a specific context.
+      </para>
+      <para>
+	The EPopupHook object is loaded by
+	the &EPlugin; system, and is used to provide dynamic extension to the
+	application context menus.
+      </para>
+      &e-popup-reference;
+
+      <!-- this looks like bum here, not sure where else to put it though -->
+      &em-popup-reference;
+    </chapter>
+
+    <chapter>
+      <title>
+	EMenu
+      </title>
+      <para>
+	The EMenu object manages the menus for a given view or component.  It
+	is used by application code to allow the plugin system an entry point
+	to current application view.  It may also be used by the application as
+	a convenience function to dynamically alter the menu system based on
+	user context.
+      </para>
+      <para>
+	The EMenuHook object is loaded by the &EPlugin; system, and is used to
+	provide dynamic extension to the application menus.
+      </para>
+      &e-menu-reference;
+    </chapter>
+
+    <chapter>
+      <title>
+	EConfig
+      </title>
+      <para>
+	The EConfig object manages the building of dynamic configuration pages
+	to configure specific application objects.  The same basic object can
+	be used to fully drive a wizard-like druid object, or to drive a
+	note-book of configuration options.  It is used by application code to
+	provide the core controller in a model-view-controller implementation
+	of a UI window.
+      </para>
+      <para>
+	The EConfigHook object is loaded by the &EPlugin; system, and is used hook
+	in additional configuration items into configuration windows or druids
+	dynamically.
+      </para>
+      &e-config-reference;
+    </chapter>
+
+    <chapter>
+      <title>
+	EEvent
+      </title>
+      <para>
+	The EEvent object manages broadcast of events for a given component or
+	application.  It is used by application code to provide the plugin
+	system with an entry point for user and system state events.
+      </para>
+      <para>
+	The EEventHook object is loaded by the &EPlugin; system, and is used hook
+	event listeners into dynamically loaded event handlers.
+      </para>
+      &e-event-reference;
+    </chapter>
+
+    <chapter>
+      <title>
+	EMFormat
+      </title>
+      <para>
+	The EMFormat object drives the formatting of MIME message content for
+	display, print, and replying.  EMFormatHTML is an implementation of
+	EMFormat which writes its output to a GtkHTML instance.
+      </para>
+      <para>
+	The EMFormatHook object is loaded by the &EPlugin; system, and is used hook
+	event listeners into dynamically loaded event handlers.
+      </para>
+      &em-format-reference;
+    </chapter>
+  </part>
+
+</book>