ejabberd is a Free and Open Source distributed fault-tolerant Jabber server.
It is writen mostly in Erlang.

The main features of ejabberd are:
	- Works on most of popular platforms: *nix
	  (tested on Linux, FreeBSD and NetBSD)
	- Distributed
	- Fault-tolerance:
	- Built-in Multi-User Chat service
	- Built-in IRC transport
	- Built-in Publish-Subscribe service
	- Built-in Jabber Users Directory service based on users vCards
	- SSL support
	- Ability to interface with external components
			(JIT, MSN-t, Yahoo-t, etc)
	- Migration from jabberd14 is possible
	- Mostly XMPP-compliant
	- Support for JEP-0030 (Service Discovery).
	- Support for JEP-0039 (Statistics Gathering).
	- Support for xml:lang attribute in many XML elements

WWW: http://www.ejabberd.im/