Add the following line to your .emacs:
(require 'eldav)
Using a proxy:
(setq eldav-proxy "http://your.proxy.server:8080")
You can access WebDAV files by preceding WebDAV URLs
with a colon:
:http://your.webdav.server/path/to/file/name
Enabling the Eldav VC feature (experimental):
(setq eldav-use-vc t)