I have successfully setup my nodes on the bbhn mesh network. I setup IAX2 trunks from my RasPBX to each node. I can connect to the nodes from an IP phone and carry on a conversation using the keypad to activate the PTT and release it.
What I haven't figured out is how to setup the system to allow a mobile or HT to connect to an IP phone. I'm not after dial tone and placement of calls but a way for folks to dial an IP phone in our ARES EOC room or another ham home if they aren't on the radio.