Decided to give Jabber a spin on ayttm with jabber.com and ran into a bit of a wall. It somehow seems like Jabber support is more or less broken in ayttm; I couldn't even get it to log in, or at least quit with an error message. It just kept 'loggin in'. Ayttm does work for gtalk though, so it's probably got something to do situations where SSL is not involved.
Update 4th Nov 2007: Heh, looks like I didn't need all that. A couple of lines was all it took to get it all to work.