Command line SIP client

This project is about make a command line SIP client using a GPL SIP source code like sofia-sip, pjsip, etc. The core program must run on Linux, either as service or as a stand alone program. A second program will be the actual command line interface, requiring some IPC. It does NOT need to support registration, authentication, audio device or multiple sip servers. The only configuration is static IP and static port on both side, only one server, and no audio device. The attached document has the detail. It's not solid rock, if minor modifications can make your work easier; I'm open to adjust the requirement, as long as important features are implemented. I am not a big fan of "owning code". If you wish to use or distribute the deliveries under GPL, you can tell and can bid accordingly.