NGN IMS clients ever available:
Boghe
Platform: Windows
web: http://code.google.com/p/boghe/
Fokus Monster
Platform: Windows, Mac OS, Linux and Win Mobile
web: http://www.monster-the-client.org/
iDoubs
Platform: iOS
web: http://code.google.com/p/idoubs/
Description: SIP/IMS VideoPhone for iOS (iPhone, iPad and iPod Touch)
IMS Communicator
Platform:
web: http://imscommunicator.berlios.de/
cvs release binary file: https://svn.berlios.de/svnroot/repos/imscommunicator/trunk/releases/
IMSDroid
Platform: android
web: http://code.google.com/p/imsdroid/
Mercuro
Platform:
web: seems to be dead
UCT IMS Client
web: http://uctimsclient.berlios.de/