All, I recently upgraded to PIAF 1.7.5.6 / 64 bit and all my trunks were not working. It seems the sip communication is not telling the other end what port to send information to. I added "bindport=5060" to my peer details and everything started working.
PBX in a Flash Version = 1.7.5.6 Running on *HARDWARE* │
│ FreePBX Version = 2.8.1.4 │
│ Running Asterisk Version = 1.8.5.0 │
│ Asterisk Source Version = 1.8.5.0 │
│ Dahdi Source Version = 2.5.0+2.5.0 │
│ Libpri Source Version = 1.4.12 │
│ IP Address = eth0 │
│ Operating System = CentOS release 5.6 (Final) │
│ Kernel Version = 2.6.18-238.9.1.el5 - 64 Bit
PBX in a Flash Version = 1.7.5.6 Running on *HARDWARE* │
│ FreePBX Version = 2.8.1.4 │
│ Running Asterisk Version = 1.8.5.0 │
│ Asterisk Source Version = 1.8.5.0 │
│ Dahdi Source Version = 2.5.0+2.5.0 │
│ Libpri Source Version = 1.4.12 │
│ IP Address = eth0 │
│ Operating System = CentOS release 5.6 (Final) │
│ Kernel Version = 2.6.18-238.9.1.el5 - 64 Bit