Hi, We discovered that PJ stack is not compatible with SER. This is may be caused by the changes done in the bug fix #371. This is due to the fact that SER do not provide the same contact in the response that in the REGISTER: REGISTER sip:proxy01.sipphone.com;transport=UDP SIP/2.0 Via: SIP/2.0/UDP 192.168.1.41:1637;rport;branch=z9hG4bKPjbbd860b613154a5eaa9fabf99c1c3ace Contact: <sip:17472769426 at 192.168.1.41:1637;transport=UDP> . SIP/2.0 200 OK Via: SIP/2.0/UDP 192.168.1.41:1637;rport=7912;branch=z9hG4bKPjbbd860b613154a5eaa9fabf99c1c3ac e;received=81.63.143.178 Contact: <sip:17472769426 at 81.63.143.178:7912;transport=UDP>;expires=1800 . I agree that the SER behavior is not standard. What can be do to solve the issue? Philippe Leuba -------------- next part -------------- An HTML attachment was scrubbed... URL: http://lists.pjsip.org/pipermail/pjsip_lists.pjsip.org/attachments/20080128/090d6972/attachment.html