hi, i have an issue that when making a call from a SIP phone going as follows: phone --> asterisk --> cisco(192.168.0.1) --> terminating voip platform(10.0.0.1) i get the cisco sending up an invite to the voip platform followed directly with a CANCEL message, as follows: Via: SIP/2.0/UDP 192.168.0.1:5060;branch=z9hG4bKF325E4 Remote-Party-ID: "device" <sip:200@192.168.0.1>;party=calling;screen=no;privacy=off From: "device" <sip:200@192.168.0.1>;tag=B2A336CC-413 To: <sip:5551234567@10.0.0.1> Date: Thu, 05 Jan 2006 15:09:08 GMT Call-ID: D8E85DC-7D3411DA-BC0AE3D2-F59304C1@192.168.0.1 Supported: 100rel,timer,resource-priority Min-SE: 1800 Cisco-Guid: 227404060-2100564442-3154699218-4120052929 User-Agent: Cisco-SIPGateway/IOS-12.x Allow: INVITE, OPTIONS, BYE, CANCEL, ACK, PRACK, UPDATE, REFER, SUBSCRIBE, NOTIFY, INFO, REG ISTER CSeq: 101 INVITE Max-Forwards: 70 Timestamp: 1136473748 Contact: <sip:200@192.168.0.1:5060> Expires: 180 Allow-Events: telephone-event Content-Type: application/sdp Content-Disposition: session;handling=required Content-Length: 285 Jan 5 15:09:10.642: //-1/xxxxxxxxxxxx/SIP/Msg/ccsipDisplayMsg: Sent: CANCEL sip:5551234567@10.0.0.1:5060 SIP/2.0 Via: SIP/2.0/UDP 192.168.0.1:5060;branch=z9hG4bKF325E4 From: "device" <sip:200@192.168.0.1>;tag=B2A336CC-413 to: <sip:5551234567@10.0.0.1> Date: Thu, 05 Jan 2006 15:09:08 GMT Call-ID: D8E85DC-7D3411DA-BC0AE3D2-F59304C1@192.168.0.1 CSeq: 101 CANCEL Max-Forwards: 70 Timestamp: 1136473750 Reason: Q.850;cause=0 Content-Length: 0 the asterisk reports the following: -- Executing Dial("SIP/200-c5c4", "SIP/5551234567@192.168.0.1") in new stack -- Called 5551234567@192.168.0.1 -- SIP/192.168.0.1-a928 is making progress passing it to SIP/200-c5c4 -- Got SIP response 500 "Internal Server Error" back from 192.168.0.1 -- SIP/192.168.0.1-a928 is circuit-busy == Everyone is busy/congested at this time (1:0/1/0) if i send it as follows: phone --> asterisk --> cisco(192.168.0.1) --> pstn all is good and call is processed normally. any help would be appreciated..