QXmpp is pretty intuitive and easy to use.  It uses Qt extensively; it is
the only third party library it depends upon.  Users need to have working
knowledge of C++ and Qt basics (Signals and Slots and Qt data types).  The
underlying TCP socket and the XMPP RFCs (RFC3920 and RFC3921) have been
encapsulated into classes and functions.  Therefore the user would not be
bothered with these details.  But it is recommended to advanced users to
read and enjoy the low level details.

WWW: http://code.google.com/p/qxmpp/