All account settings reside in the variable
Usually you only need to set the JID, in the form
‘username@server’ (or ‘username@server/resource’ to use a
specific resource name). These are the other account options:
jabber-connect-allwill not attempt to connect it. You can still connect it manually with
starttls), which means that encryption is activated if the server supports it. The other possibilities are “unencrypted” (
network), which means just that, and “legacy SSL/TLS” (
ssl), which means that encryption is activated on connection.
If you have a very new version of dns.el,1 you can connect to Google Talk just by specifying your Gmail address as JID. Otherwise, you also need to set “network server” to talk.google.com and “connection type” to “legacy SSL”.
Previous versions of jabber.el had the variables
jabber-password. These are now obsolete and not used.
 Specifically, you need Emacs 23, or No Gnus 0.3.