le fragment avant BYE, j'avais allégé le principal
Code:
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U 2014/02/06 22:38:13.563511 91.121.129.20:5962 -> 192.168.1.17:5060
  OPTIONS sip:0033184230751@89.83.76.95:5060 SIP/2.0..Call-ID: 02-06056-11ee761d-30f885bb2@91.121.129.20..Contact: <sip:91.121.129.20:5962>.
  .CSeq: 1 OPTIONS..From: <sip:keepalive@91.121.129.20:5962>;tag=02-06056-11ee761c-6e5254b02..Max-Forwards: 70..To: <sip:0033184230751@sip.o
  vh.fr>..Via: SIP/2.0/UDP 91.121.129.20:5962;rport;branch=z9hG4bK-DNRU-098965e1-5bd808ae..Content-Length: 0....                            
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U 2014/02/06 22:38:13.564046 192.168.1.17:5060 -> 91.121.129.20:5962
  SIP/2.0 200 OK..Via: SIP/2.0/UDP 91.121.129.20:5962;branch=z9hG4bK-DNRU-098965e1-5bd808ae;received=91.121.129.20;rport=5962..From: <sip:ke
  epalive@91.121.129.20:5962>;tag=02-06056-11ee761c-6e5254b02..To: <sip:0033184230751@sip.ovh.fr>;tag=as3df48ac0..Call-ID: 02-06056-11ee761d
  -30f885bb2@91.121.129.20..CSeq: 1 OPTIONS..Server: Asterisk PBX 10.7.0..Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, SUBSCRIBE, NOTIFY
  , INFO, PUBLISH..Supported: replaces, timer..Contact: <sip:89.83.76.95:5060>..Accept: application/sdp..Content-Length: 0....              
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U 2014/02/06 22:38:16.611166 91.121.129.20:5060 -> 192.168.1.17:5060
  SIP/2.0 200 OK..Call-ID: 0b4784ac3a062ee653620cd871778558@sip.ovh.fr..Contact: <sip:10.7.1.65:5060>..Content-Type: application/sdp..CSeq: 
  103 INVITE..From: "400" <sip:0033183626986@sip.ovh.fr>;tag=as04af75a1..Record-Route: <sip:91.121.129.20:5060;transport=udp;lr>..To: <sip:0
  148734812@sip.ovh.fr>;tag=00-08179-013e5730-4d9162956..Via: SIP/2.0/UDP 192.168.1.17:5060;received=89.83.76.95;rport=5060;branch=z9hG4bK18
  176b4a..Allow: UPDATE,REFER,INFO..Server: Cirpack/v4.56 (gw_sip)..Content-Length: 265....v=0..o=cp10 139172266333 139172266334 IN IP4 10.7
  .1.129..s=SIP Call..c=IN IP4 91.121.129.140..t=0 0..m=audio 33768 RTP/AVP 0 8 101..b=AS:77..a=rtpmap:0 PCMU/8000/1..a=rtpmap:8 PCMA/8000/1
  ..a=rtpmap:101 telephone-event/8000..a=fmtp:101 0-15..a=ptime:30..a=sendrecv..                                                            
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U 2014/02/06 22:38:16.611380 192.168.1.17:5060 -> 91.121.129.20:5060
  ACK sip:10.7.1.65:5060 SIP/2.0..Via: SIP/2.0/UDP 89.83.76.95:5060;branch=z9hG4bK716fde7c;rport..Route: <sip:91.121.129.20:5060;transport=u
  dp;lr>..Max-Forwards: 70..From: "400" <sip:0033183626986@sip.ovh.fr>;tag=as04af75a1..To: <sip:0148734812@sip.ovh.fr>;tag=00-08179-013e5730
  -4d9162956..Contact: <sip:0033183626986@89.83.76.95:5060>..Call-ID: 0b4784ac3a062ee653620cd871778558@sip.ovh.fr..CSeq: 103 ACK..User-Agent
  : Asterisk PBX 10.7.0..Content-Length: 0....                                                                                              
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U 2014/02/06 22:38:20.607997 91.121.129.20:5060 -> 192.168.1.17:5060
  SIP/2.0 200 OK..Call-ID: 0b4784ac3a062ee653620cd871778558@sip.ovh.fr..Contact: <sip:10.7.1.65:5060>..Content-Type: application/sdp..CSeq: 
  103 INVITE..From: "400" <sip:0033183626986@sip.ovh.fr>;tag=as04af75a1..Record-Route: <sip:91.121.129.20:5060;transport=udp;lr>..To: <sip:0
  148734812@sip.ovh.fr>;tag=00-08179-013e5730-4d9162956..Via: SIP/2.0/UDP 192.168.1.17:5060;received=89.83.76.95;rport=5060;branch=z9hG4bK18
  176b4a..Allow: UPDATE,REFER,INFO..Server: Cirpack/v4.56 (gw_sip)..Content-Length: 265....v=0..o=cp10 139172266333 139172266334 IN IP4 10.7
  .1.129..s=SIP Call..c=IN IP4 91.121.129.140..t=0 0..m=audio 33768 RTP/AVP 0 8 101..b=AS:77..a=rtpmap:0 PCMU/8000/1..a=rtpmap:8 PCMA/8000/1
  ..a=rtpmap:101 telephone-event/8000..a=fmtp:101 0-15..a=ptime:30..a=sendrecv..                                                            
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U 2014/02/06 22:38:20.608213 192.168.1.17:5060 -> 91.121.129.20:5060
  ACK sip:10.7.1.65:5060 SIP/2.0..Via: SIP/2.0/UDP 89.83.76.95:5060;branch=z9hG4bK5e34cf81;rport..Route: <sip:91.121.129.20:5060;transport=u
  dp;lr>..Max-Forwards: 70..From: "400" <sip:0033183626986@sip.ovh.fr>;tag=as04af75a1..To: <sip:0148734812@sip.ovh.fr>;tag=00-08179-013e5730
  -4d9162956..Contact: <sip:0033183626986@89.83.76.95:5060>..Call-ID: 0b4784ac3a062ee653620cd871778558@sip.ovh.fr..CSeq: 103 ACK..User-Agent
  : Asterisk PBX 10.7.0..Content-Length: 0....                                                                                              
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