XMPP on the wen with PHP :
XMPPHP is the successor to Class.Jabber.PHP that I've been promising for years. Taking advantage of PHP5, I believe it to be an elegant solution with a direct approach.
Some of the features include:
Connect to any XMPP 1.0 server (Google Talk, LJ Talk, jabber.org, etc)
Supports TLS encryption
Several XML processing approaches and supported styles (process indefinitely, processUntil an event, processTime for a number of seconds), waiting on events or map them, etc.