Sofia-SIP is an open-source SIP User-Agent library, compliant with the 
IETF RFC3261 specification. It can be used as a building block for SIP 
client software for uses such as VoIP, IM, and many other real-time and
person-to-person communication services. The primary target platform for
Sofia-SIP is GNU/Linux. Sofia-SIP is based on a SIP stack developed at
the Nokia Research Center. Sofia-SIP is licensed under the LGPL.
