YATE-based universal telephony client

 YATE is a telephony engine aimed at creating a telephony server that
 performs well enough to deal with PBX requirements and also flexible
 enough for complex Gateway and IVR solutions.
 .
 YateClient is an Instant Messenger and a SoftPhone.
 .
 Supported Instant Messaging Providers
  Google talk/Google Voice
  Facebook chat
  jabber.org
 .
 Supported Telephony Protocols
  Jingle/ Google Talk/ XMPP
  Session Initiation Protocol (SIP)
  Packet-based multimedia communications systems (H.323)
  Inter-Asterisk eXchange protocol (IAX)