JClaim

JClaim was released for first public use on the 3rd August 2007. It is a multiprotocol instant messaging application for any OS supporting Java 1.5 or better (Windows, Mac OS X, Linux, Solaris). It connects users to multiple IM services, such as AIM, ICQ, Windows Live Messenger, Yahoo! Messenger, XMPP, Nate and a few others.

Can be used as a java library to create other software that can connect to any of the supported IM protocols (see link below).

Project is released under GPL2 software license and is available from Sourceforge.net for download, including source code (see link below).

Features

Cross-Platform: Runs on Windows, Macintosh, Linux, Solaris.
Connectivity to AIM (Chatting, File Transfers, Icons), ICQ (Chatting), Yahoo! Messenger (Chatting, File Transfers),MSN (Chatting), Nate(Chatting), XMPP (Chatting), Facebook (Chatting), GoogleTalk (Chatting)chatting networks.
Web server. Allows access to your messenger from a web enabled phone or from a simplest web browser (thin client). Connect to your contacts from anywhere.
Spell checks as you type.
No banners or ads.
Weather updates.
Integrated Desktop search and Web search.
No local installation. Automatic software updates.
Security and Virus Protection enhancements. Keeps your business safe from viruses and malicious code.
Logging and auditing in accordance with such regulations as SEC 17a-4, NASD 3010, Sarbanes-Oxley, HIPAA, Gramm-Leach-Bliley and Freedom of Information Act. (Please consult your compliance department.)
Ultimate in administration flexibility. Set up defaults or lock down specific harmful settings for the entire site. Locked settings will not be seen by users. Make your environment safer by turning off harmful features like file downloads.

(Framework can be used independently to design your own software which needs listed functionality).

Cross-Platform! Runs on Windows, Macintosh, Linux, Solaris.
Connectivity to AIM (Chatting, File Transfers, Icons), ICQ (Chatting), Yahoo! (Chatting, File Transfers),MSN (Chatting), XMPP (Chatting), Facebook, GoogleTalk (Chatting)chatting networks.
Weather updates. From this, you can gather that Connection framework is very flexible and does not have to be an IM network.
API for sending cell phone messages (only certain providers), but feel free to add more.
Included is a miniature servlet engine which can be used to create remote interfaces usable by a full web browser or a web enabled cell phone.