SIP proxy/redirect/registrar

 Siproxd is a proxy/masquerading daemon for the SIP (Session
 Initiation Protocol) which is used in IP telephony.
 It handles registrations of SIP clients on a private IP network
 and performs rewriting of the SIP message bodies to make SIP
 connections possible via a masquerading firewall.
 It allows SIP clients (like kphone, linphone) to work behind
 an IP masquerading firewall or router.