FacebookIM or short FIM is a facebook chat client for Windows Mobile.

Features:

* Facebook Chat
* Photo / Video Uploads directly from your device
* Integrated m.facebook.com browser
* Status Updates
* Chat Message Notifications
* Facebook New Notification indicator
* Unread Inbox Message Indicator
* AppToDate Support
* All Video Modes Friendly
* Touch Friendly
* No 3rd party registration is needed, this app connected directly to the Facebook website.

http://forum.xda-developers.com/showthread.php?t=480365