Trillian version one and two are both very unstable. The developers should at the very least have a central place to triage their bugs instead of having everyone whine about things not operating correctly. Why people bought it, I'll never understand (this coming from a computer programmer and not your average Joe Schmo user).
I use Jabber to communicate, although I do not know anyone who actively uses the Jabber protocol ( care to add me? I'm
trache@myjabber.net ). Individual Jabber servers are listed at
http://www.jabber.org/user/publicservers.php
There are gateways to every major instant messaging protocol, so you can still communicate with others.
I personally use JAJC as a client, located at
http://jajc.ksn.ru/ but you can pick your client of choice at
http://www.jabber.org/software/clients.php
It does the same, if not more than Trillian, and has proven to be less prone to bugs than Trillian. All of JAJC's functionality is free to use, but unfortunately due to some of the libraries that have been incorporated into its development, it is not open-source.