Overview
Facebook Chat is now available using the XMPP ("Jabber") protocol. This is different than the built-in Facebook Chat capability of Trillian's included Facebook plugin. At this moment we are providing these instructions for those of you that wish to start using the newly available XMPP connection method immediately. Be sure you have downloaded and installed Trillian 4.1 build 24 or later.
Getting started
You'll need to set up a username with Facebook by visiting http://facebook.com/username. Note that you may already have a username. After creating a username, you must sign out of Facebook and sign back in in order to enable the username.
Why do I need a username to use Facebook Chat over XMPP?
You need a username because you must be identified with your Facebook username@chat.facebook.com in order for Facebook Chat to operate properly with Trillian. The email address you use to sign in to Facebook will not work.
Adding the connection to Trillian
Go into Trillian Preferences > Identities & Connections.
Click Add a new connection.
Choose Jabber/XMPP.
In the username field, enter your full JID e.g. your_facebook_username@chat.facebook.com
Note: You must enter your username in all lowercase letters in place of "your_facebook_username" shown above.
Enter your Facebook password in the password field.
Don't forget to check the box "[X] Automatically connect to this account at startup" if you want to connect every time you load Trillian.
When you're finished, press Connect.
Troubleshooting
If you are receiving two messages every time somebody messages you or when you message people, this could be due to the fact that you still have Facebook Chat turned on in Trillian's Facebook plugin. To turn that off simply remove your username and password from the Facebook connection.
If your username is not being accepted by Facebook then make sure you're not using an email address; you must set up a username with Facebook.
Help and resources from Facebook
You can find more help in Facebook's Help Center page on using Facebook Chat: http://www.facebook.com/help/?topic=chatclient