да вот так
можно выставить глобально
ignoreregexpire=yes
в пире
qualify=yes
Затем:13:39:43.485337 IP (tos 0x68, ttl 63, id 29440, offset 0, flags [none], proto UDP (17), length 653)
192.168.0.31.5060 > 192.168.4.2.5060: SIP, length: 625
REGISTER sip:192.168.4.2 SIP/2.0
Contact: "ivuts" <sip:104@192.168.0.31:5060>;expires=3600
13:39:43.486052 IP (tos 0x60, ttl 64, id 45516, offset 0, flags [none], proto UDP (17), length 571)
192.168.4.2.5060 > 192.168.0.31.5060: SIP, length: 543
SIP/2.0 200 OK
Expires: 3600
Вам не кажется это странным ?14:26:35.478829 IP (tos 0x68, ttl 63, id 30195, offset 0, flags [none], proto UDP (17), length 653)
192.168.0.31.5060 > 192.168.4.2.5060: SIP, length: 625
REGISTER sip:192.168.4.2 SIP/2.0
Contact: "ivuts" <sip:104@192.168.0.31:5060>;expires=3600
14:26:35.499462 IP (tos 0x60, ttl 64, id 45533, offset 0, flags [none], proto UDP (17), length 571)
192.168.4.2.5060 > 192.168.0.31.5060: SIP, length: 543
SIP/2.0 200 OK
Expires: 3600