reSIProcate SIP stack - click-to-call utility

 sipdialer is a click-to-call application that uses the SIP REFER
 method to force a SIP phone (for example, the phone on your desk)
 to dial another number. It can be registered in GConf to handle
 clicks on sip:, sips: and tel: URIs in other applications and the
 web browser.
 .
 reSIProcate is a framework that aims to fully implement the SIP protocol
 in first class C++. It is intended for use in other applications,
 such as the repro SIP proxy.