All calls through any gateway are terminating after 38 seconds:
[7] 2012/10/17 16:18:34: Call de4c6373@pbx: Clear last INVITE
[5] 2012/10/17 16:18:34: INVITE Response 487 Request Terminated: Terminate de4c6373@pbx
[8] 2012/10/17 16:18:34: Remove leg 535: call port 22, SIP call id de4c6373@pbx
[8] 2012/10/17 16:18:34: Clearing call port 22, SIP call id de4c6373@pbx
[6] 2012/10/17 16:18:34: Call port 17: Different Codecs (local , remote pcmu/8000), callid call-7141227A-9FFA-2F10-0803-86@192.168.18.8, falling back to transcoding
[8] 2012/10/17 16:18:37: Packet authenticated by transport layer
[5] 2012/10/17 16:18:42: The call port 21 - 30 seconds callback set for force cleanup
[8] 2012/10/17 16:18:42: Packet authenticated by transport layer
[8] 2012/10/17 16:18:47: Last message repeated 7 times
[9] 2012/10/17 16:18:47: Resolve 13590: aaaa udp 192.168.18.48 5060
[9] 2012/10/17 16:18:47: Resolve 13590: a udp 192.168.18.48 5060
[9] 2012/10/17 16:18:47: Resolve 13590: udp 192.168.18.48 5060
[9] 2012/10/17 16:19:03: Resolve 13591: aaaa udp 192.168.18.48 5060
[9] 2012/10/17 16:19:03: Resolve 13591: a udp 192.168.18.48 5060
[9] 2012/10/17 16:19:03: Resolve 13591: udp 192.168.18.48 5060
[9] 2012/10/17 16:19:08: Resolve 13592: aaaa udp 192.168.18.48 5060
[9] 2012/10/17 16:19:08: Resolve 13592: a udp 192.168.18.48 5060
[9] 2012/10/17 16:19:08: Resolve 13592: udp 192.168.18.48 5060
[9] 2012/10/17 16:19:08: Resolve 13593: aaaa udp 192.168.18.48 5060
[9] 2012/10/17 16:19:08: Resolve 13593: a udp 192.168.18.48 5060
[9] 2012/10/17 16:19:08: Resolve 13593: udp 192.168.18.48 5060
[8] 2012/10/17 16:19:12: Clearing call port 21, SIP call id eb81f86f@pbx
[5] 2012/10/17 16:19:12: Terminating call 21
[5] 2012/10/17 16:19:12: The call port 21 was erased forcefully