[Serusers] mediaproxy problem

Dear sirusers, The following is my log file kept by x-lite. SEND TIME: 15466254 SEND >> ipaddress1:5060 INVITE sip:8103@ipaddress1 SIP/2.0 Via: SIP/2.0/UDP ip address2:5060;rport;branch=z9hG4bKEA15D2B6122C11D9B04300E04CEE03A2 From: 8103 <sip:8103@ip address1>;tag=1235055289 To: <sip:8103@ip address1> Contact: <sip:8103@ipaddress1:5060> Call-ID: EA15D2B5-122C-11D9-B043-00E04CEE03A2(a)192.168.1.13 CSeq: 52555 INVITE Max-Forwards: 70 Content-Type: application/sdp User-Agent: X-Lite release 1103m Content-Length: 137 v=0 o=8103 15466182 15466249 IN IP4 ipaddress2 s=X-Lite c=IN IP4 ipaddress2 t=0 0 m=audio 8000 RTP/AVP 0 a=rtpmap:0 pcmu/8000 RECEIVE TIME: 15466262 RECEIVE << ipaddress1:5060 SIP/2.0 100 trying -- your call is important to us Via: SIP/2.0/UDP ipaddress2:5060;rport=19465;branch=z9hG4bKEA15D2B6122C11D9B04300E04CEE03A2 From: 8103 <sip:8103@ipaddress1>;tag=1235055289 To: <sip:8103@ipaddress1> Call-ID: EA15D2B5-122C-11D9-B043-00E04CEE03A2(a)192.168.1.13 CSeq: 52555 INVITE Server: Sip EXpress router (0.8.14 (i386/linux)) Content-Length: 0 Warning: 392 ipaddress1:5060 "Noisy feedback tells: pid=2307 req_src_ip=219.137.9.30 req_src_port=19465 in_uri=sip:8103@ipaddress2 out_uri=sip:8103@ipaddress2:5060 via_cnt==1" I use the URI to call back to myself. But it just try. I wonder if this happens when the NAT was set improperly. If so,how can I make some changes? Thanks in advance. Sincerely, Kun