A while ago, I made a shitty Miranda plugin in which it was hard-coded to log into a specific zone with a username/password, hide in a subarena, and just do private/chat messages only. After a while, I stopped using it because I stopped running out of times in which I needed to talk with people in Subspace without actually being in it.
With the Chat Protocol, it should be a snap to quickly patch together a plugin for almost any of the IM clients. In fact, you should make it a Jabber extension and just use that instead. Jabber is so much nicer, just no one actually uses it for Jabber.