I am not so good at helping with Trillian, but you can use http://www.meebo.com without signing up or downloading (just sign in on the AIM slot, not the Meebo one) and Meebo usually works pretty well.

>.> It also has a feature that translates what you say into pirate speak (pirateon and pirateoff) and is luvverly. I always use it at school.

:D!

Luck,

-TL