It’s pretty obvious now this blog is closed. Almost 3 years without posting. In case you don’t know, a couple of years ago support for MFC-R2 signaling into Asterisk was integrated natively into chan_dahdi/chan_zap, which effectively meant chan_unicall was not needed anymore for MFC-R2. Asterisk versions starting with 1.6.2 use the OpenR2 library (www.libopenr2.org), no patching needed.
I’ll leave the blog online as a reference and memories of the good old Unicall times