ichat server, jabber
hey, deeje.. found on the mac os x tiger server overview
iChat Server
To ensure secure instant messaging in your organization, Tiger Server enables you to host a private iChat Server that integrates with your existing directory services for user accounts and authentication. iChat Server uses the XMPP protocol popularized by the open-source Jabber project and SSL/TLS encryption to protect internal communications. And because it’s based on open standards, iChat Server works with Tiger’s iChat AV and with popular Jabber clients on Windows, Linux and PDAs.