1. Openfire

... instant messaging, XMPP (also called Jabber). Openfire is incredibly easy to setup and administer, but offers rock-solid security and performance. Visit Openfire! ...

2. OLAT

...  Jabber client Authentication Options Users can create their own accounts (with/without approval by administrators) Direct login into OLAT with OLAT user name ...

3. Miranda IM

...  AIM (AOL Instant Messenger) Gadu-Gadu IAX (Inter-Asterisk Exchange) ICQ IRC (Internet Relay Chat) Jabber MSN Netsend Tlen Yahoo And more... Supported Operating Systems Windows ...

4. Pidgin

Pidgin is an instant messaging program for Windows, Linux, BSD, and other Unixes. You can talk to your friends using AIM, ICQ, Jabber/XMPP, MSN Messenger, Yahoo!, Bonjour, Gadu-Gadu, IRC, Novell GroupWise ...

5. Spark

Spark is an Open Source, cross-platform IM client optimized for businesses and organizations. It features built-in support for group chat, telephony integration, and strong security. ...

6. WengoPhone

... more than just VoIP software: it is a full-fledged communications tool that lets you enjoy free calls, video conferencing, SMS, chat over many existing protocols (MSN, AIM/ICQ, Yahoo!, Jabber)... Visit ...

7. Gizmo5

... on Gizmo5, MSN, AIM, Yahoo! and Jabber for free. File Sharing Easy sharing of photos, videos and files from your mobile phone or computer. Video Calls See friends and family when making calls anywhere ...