Free and Open Source distributed fault-tolerant Jabber server which is mostly written in Erlang and runs on many platforms.

A Java based configuration tool for the Jabber.org jabber daemon.

Cross-platform, open source XMPP server written in Java, with web based administration.

Open source Jabber server implementation aiming to produce a fast, simple, and efficient server with modularisation.

A lightweight, open source Jabber server. It is written in Lua and aims to be easy to configure, use, and extend.