Sorry, I post it in the wrong way.. Hi guys, I've got this problem while receiving REGISTER packets from an IP Phone on my proxy/registrar. At the beginning the registration process goes fine (I do authentication in the right way), but at the next registrations something goes wrong and I receive the following message: 10:36:03.423 sip_transport.c Error processing 485 bytes packet from UDP 62.94.0.199:22934 : PJSIP syntax error exception when parsing 'Expires' header on line 9 col -1: REGISTER sip:voip.domain.it SIP/2.0 Via: SIP/2.0/UDP 62.94.0.199:22934;rport;branch=z9hG4bK14b2b284e2 From: "07611765207" <sip:07611765207@xxxxxxxxxxxxxx>;tag=3079ec23 To: "07611765207" <sip:07611765207 at voip.domain.it> Call-ID: 3212d56f727a841749763cb8718c79b5 at 62.94.0.199 Contact: <sip:07611765207 at 62.94.0.199:22934> CSeq: 1 REGISTER Max-Forwards: 70 Expires: Allow: INVITE,CANCEL,ACK,BYE,NOTIFY,REFER,OPTIONS,INFO,MESSAGE User-Agent: CM5K 706198U Content-Length: 0 I suppose there's a problem while parsing the Expires field, which (after the first time) comes empty to the proxy, for some reason I don't know ... It's a bug or something I can adjust working on parsing the packet in sip_transport.c? Cheers, Giusy -