After putting this off by several weeks, I finally spent some quality time working in getting to work OpenZAP with OpenR2. The result is now available in the openzap project svn trunk:
http://svn.openzap.org/svn/openzap/trunk/
I also created some basic documentation about how to set it up: http://wiki.freeswitch.org/wiki/OpenZAP_OpenR2
This means that from now on FreeSWITCH will support MFC-R2 signaling with the same stack that Asterisk is using since 1.6.2
I still need to do some work on the documentation and lots of stress testing, but you can start playing with it and bugging me if it does not work 🙂