[SR-Users] BAD request

Hi, Can anybody help why 'BAD request' is sent for the Invite? Thanks a lot Amar SeqNO: 22155, Time:2012-10-5 14:28:16, RECEIVED MSG FROM OTHERSS Sender<-->Receiver:109.169.25.9:5060 <---> 103.10.31.251:5060 INVITE sip:9779841512112@103.10.31.251:5060 SIP/2.0 Max-Forwards: 69 From: "147963" <sip:84473@sip58.dial2dayplus.us>;tag=T-mDbiFHTcemPwtrCSksCpvl0mJ8HaI5 To: <sip:9779841512112@103.10.31.251:5060> Call-ID: gx.R3nZ.4.1-N4oFwOqQ1zQ0SAj8vseQ CSeq: 29171 INVITE Allow: PRACK,INVITE,ACK,BYE,CANCEL,UPDATE,SUBSCRIBE,NOTIFY,REFER,MESSAGE,OPTIONS Session-Expires: 1800 Min-SE: 90 P-hint: outbound Supported: timer Via: SIP/2.0/UDP 109.169.25.9:5060;branch=z9hG4bK1349426396705 Contact: <sip:109.169.25.9:5060> Expires: 300 Record-Route: <sip:109.169.25.9;lr=on> Content-Type: application/sdp Content-Length: 233 v=0 o=- 3558415916 3558415916 IN IP4 42.108.33.29 s=pjmedia c=IN IP4 195.219.14.151 t=0 0 m=audio 21556 RTP/AVP 18 101 a=rtpmap:18 G729/8000 a=fmtp:18 annexb=no a=sendrecv a=rtpmap:101 telephone-event/8000 a=fmtp:101 0-15 SeqNO: 22156, Time:2012-10-5 14:28:16, SEND MSG TO OTHERSS Sender<-->Receiver:103.10.31.251:5060 <---> 109.169.25.9:5060 SIP/2.0 400 Bad Request Via: SIP/2.0/UDP 109.169.25.9:5060;branch=z9hG4bK1349426396705 CSeq: 29171 INVITE From: "147963" <sip:84473@sip58.dial2dayplus.us>;tag=T-mDbiFHTcemPwtrCSksCpvl0mJ8HaI5 To: <sip:9779841512112@103.10.31.251:5060>;tag=8 X-ZTE-Cause: "SBC-5442" Call-ID: gx.R3nZ.4.1-N4oFwOqQ1zQ0SAj8vseQ Content-Length: 0