Facebook has been working on Jabber support for Facebook Chat for a while, but it appears the service may be closer to launching. IM server company Process One says their bot has just detected Facebook’s deployment of the XMPP stack on chat.facebook.com.

Facebook has previously said the Jabber interface to Facebook Chat will allow users to:

• Chat with friends inside Facebook from the client of their choosing, like Google Talk
• See which of their friends are online and view their profile pictures
• Set their status

For developers, this could mean that Facebook’s Chat Invite API could become more powerful, as more Facebook users would be able to receive synchronous app requests even if they’re not on Facebook.com.