[Serusers] "400 Bad Request" Message problem

Hi!! We work with ser 0.8.14, and mediaproxy. As clients we are using two Windows Messenger 4.7 in two different ADSL (NATed) lines connecting to SER in a public Internet address. The scenario is as follows: The sip server is listening on 194.179.25.55. The user chano@ wmserver.hi.inet on the machine sayuritra (private address: 172.26.0.52, public address: 217.125.212.22) calls to the user raquel(a)wmserver.hi.inet on hobbes (private address: 192.168.1.34, public addess: 80.32.97.245). The messages captured in the sip server are the following: U 217.125.212.22:10094 -> 194.179.25.55:5060 INVITE sip:raquel@wmserver.hi.inet SIP/2.0..Via: SIP/2.0/UDP 172.26.0.52:13552.. From: "chano" <sip:chano@wmserver.hi.inet>;tag=181d13b4-e1f 0-4dbd-9606-18e52b57dbf6..To: <sip:raquel@wmserver.hi.inet>. .Call-ID: ab9bb0f1-3a43-4ecd-a787-03a439714bda@172.26.0.52..CSeq: 1 INVITE.. Contact: <sip:172.26.0.52:13552>..User-Agent: Windows RTC/1.0..Content-Type: application/sdp.. Content-Length: 529....v=0..o=sayuritra 0 0 IN I P4 172.26.0.52..s=session..c=IN IP4 172.26.0.52..b=CT:1000..t=0 0.. m=audio 38370 RTP/AVP 97 111 112 6 0 8 4 5 3 101..a=rtpmap:97 red/8000.. a=rtpmap:111 SIREN/16000..a=fmtp:111 bitrate=16000..a=rtpmap:112 G7221/16000. .a=fmtp:112 bitrate=24000..a=rtpmap:6 DVI4/16000..a=rtpmap:0 PCMU/8000..a=rtpmap:8 PCMA/8000..a=rtpmap:4 G723/8000. .a=rtpmap:5 DVI4/8000..a=rtpmap:3 GSM/8000..a=rtpmap:101 telephone- event/8000..a=fmtp: 101 0-16..m=video 14490 RTP/AVP 34 31..a=rtpmap:34 H263/90000..a=rtpmap:31 H261/90000.. U 194.179.25.55:5060 -> 217.125.212.22:10094 SIP/2.0 100 trying -- your call is important to us..Via: SIP/2.0/UDP 172.26.0.52:13552; rport=10094;received=217.125.212.22..From: "chano" <sip:chano@wmserver.hi.inet>; tag=181d13b4-e1f0-4dbd-9606-18e52b57dbf6..To: <sip:raquel@wmserver.hi.inet>..Call-ID: ab9bb0f1-3a43-4ecd-a787-0 3a439714bda@172.26.0.52..CSeq: 1 INVITE..Server: Sip EXpress router (0.8.14 (i386/linux)).. Content-Length: 0..Warning: 392 194.179.25.55:50 60 "Noisy feedback tells: pid=987 req_src_ip=217.125.212.22 req_src_port=10094 in_uri=sip:raquel@wmserver.hi.inet out_uri=sip:80.32.97.245:10052 via_cnt==1".... U 194.179.25.55:5060 -> 80.32.97.245:10052 INVITE sip:80.32.97.245:10052 SIP/2.0..Max-Forwards: 10..Record- Route: <sip:raquel@194.179.25.55;ftag=181d13b4-e1f0-4dbd- 960618e52b57dbf6;lr>..Via: SIP/2.0/UDP 194.179.25.55;branch=z9hG4bK8f9a.26d2ad44.0..Via: SIP/2.0/UDP 172.26.0.52:13552;rport=10094;received=217.125.212.22..From: "chano" <sip:chano@wmserver.hi.inet>;tag=181d13b4-e1f0-4dbd-9606- 18e52b57dbf6..To: <sip:raquel@wmserver.hi.inet>..Call-ID: ab9bb0f1- 3a43-4ecd-a787-03a439714bda@172.26.0.52..CSeq: 1 INVITE..Contact: <sip:217.125.212.22:10094>..User-Agent: Windows RTC/1.0..Content-Type: application/sdp..Content-Length: 529....v=0..o=sayuritra 0 0 IN IP4 172.26.0.52..s=session..c=IN IP4 172.26.0.52..b=CT:1000..t=0 0..m=audio 38370 RTP/AVP 97 111 112 6 0 8 4 5 3 101..a=rtpmap:97 red/8000..a=rtpmap:111 SIREN/16000..a=fmtp:111 bitrate=16000..a=rtpmap:112 G7221/16000..a=fmtp:112 bitrate=24000..a=rtpmap:6 DVI4/16000..a=rtpmap:0 PCMU/8000..a=rtpmap:8 PCMA/8000..a=rtpmap:4 G723/8000..a=rtpmap:5 DVI4/8000..a=rtpmap:3 GSM/8000..a=rtpmap:101 telephone-event/8000..a=fmtp:101 0-16..m=video 14490 RTP/AVP 34 31..a=rtpmap:34 H263/90000..a=rtpmap:31 H261/90000.. U 80.32.97.245:10052 -> 194.179.25.55:5060 SIP/2.0 100 Trying..Via: SIP/2.0/UDP 194.179.25.55;branch=z9hG4bK8f9a.26d2ad44.0..Via: SIP/2.0/UDP 172.26.0.52:13552;rport=10094;received=217.125.212.22..From: "chano" <sip:chano@wmserver.hi.inet>;tag=181d13b4-e1f0-4dbd-9606- 18e52b57dbf6..To: <sip:raquel@wmserver.hi.inet>;tag=4410fcfd-ae51-494e- a0ff-47c34ab309cb..Call-ID: ab9bb0f1-3a43-4ecd-a787- 03a439714bda@172.26.0.52..CSeq: 1 INVITE..User-Agent: Windows RTC/1.0..Content-Length: 0.... U 80.32.97.245:10052 -> 194.179.25.55:5060 SIP/2.0 400 Bad Request..Via: SIP/2.0/UDP 194.179.25.55;branch=z9hG4bK8f9a.26d2ad44.0..Via: SIP/2.0/UDP 172.26.0.52:13552;rport=10094;received=217.125.212.22..From: "chano" <sip:chano@wmserver.hi.inet>;tag=181d13b4-e1f0-4dbd-9606- 18e52b57dbf6..To: <sip:raquel@wmserver.hi.inet>;tag=4410fcfd-ae51-494e- a0ff-47c34ab309cb..Call-ID: ab9bb0f1-3a43-4ecd-a787- 03a439714bda@172.26.0.52..CSeq: 1 INVITE..Record-Route: <sip:raquel@194.179.25.55;ftag=181d13b4-e1f0-4dbd-9606-18e52b57dbf6;lr> ..User-Agent: Windows RTC/1.0..Content-Length: 0.... My ser.cfg is: debug=3 # debug level (cmd line: -dddddddddd) fork=yes log_stderror=yes # (cmd line: -E) check_via=no # (cmd. line: -v) dns=no # (cmd. line: -r) rev_dns=no # (cmd. line: -R) port=5060 children=4 fifo="/tmp/ser_fifo" listen=194.179.25.55 loadmodule "/usr/lib/ser/modules/postgres.so" loadmodule "/usr/lib/ser/modules/sl.so" loadmodule "/usr/lib/ser/modules/tm.so" loadmodule "/usr/lib/ser/modules/rr.so" loadmodule "/usr/lib/ser/modules/maxfwd.so" loadmodule "/usr/lib/ser/modules/usrloc.so" loadmodule "/usr/lib/ser/modules/textops.so" loadmodule "/usr/lib/ser/modules/registrar.so" loadmodule "/usr/lib/ser/modules/uri.so" loadmodule "/usr/lib/ser/modules/domain.so" loadmodule "/usr/lib/ser/modules/mediaproxy.so" loadmodule "/usr/lib/ser/modules/auth.so" loadmodule "/usr/lib/ser/modules/auth_db.so" modparam("usrloc", "db_mode", 2) modparam("usrloc", "user_column", "user_id") modparam("usrloc", "db_url", "sql://ser:ser@localhost:5432/ser") modparam("auth_db", "user_column", "user_id") modparam("auth_db", "db_url", "sql://ser:ser@localhost:5432/ser") modparam("auth_db", "calculate_ha1", yes) modparam("auth_db", "password_column", "password") modparam("domain", "db_mode", 1) modparam("domain", "domain_table", "subscriber") modparam("domain", "db_url", "sql://ser:ser@localhost:5432/ser") modparam("uri", "db_url", "sql://ser:ser@localhost:5432/ser") modparam("uri", "uri_table", "uri") modparam("uri", "uri_user_column", "user_id") modparam("mediaproxy", "natping_interval", 60) modparam("registrar", "nat_flag", 2) route{ if (!mf_process_maxfwd_header("10")) { if (method!="ACK") { sl_send_reply("483", "Too many hops"); }; break; }; if (msg:len >= max_len) { if (method!="ACK") { sl_send_reply("513", "Message too big"); }; break; }; if (method=="REGISTER") { if (is_from_local()) { # Mark as NAT'ed if (client_nat_test("3")) { setflag(2); force_rport(); fix_contact(); }; if (!www_authorize("wmserver.hi.inet", "subscriber")) { www_challenge("wmserver.hi.inet", "0"); break; } else if (!check_to()) { sl_send_reply("403", "Username!=To not allowed"); break; }; if (!save("location")) { sl_reply_error(); }; } else { sl_send_reply("403", "This domain is not served here"); }; break; }; if (method=="INVITE") { if (!(is_from_local() || is_uri_host_local())) { sl_send_reply("403", "Relaying is forbidden"); break; }; t_on_failure("1"); } else if (method == "BYE" || method == "CANCEL") { end_media_session(); }; if (loose_route()) { if (method=="INVITE" || method=="ACK") { use_media_proxy(); }; # end media session for BYE and CANCEL is done above # before entering the loose route. no need to call it here t_relay(); break; }; # Force subsequent messages to pass trough this proxy if (method == "INVITE") { record_route(); }; if (client_nat_test("3") && !search("^Record-Route:")) { # Mark as NAT'ed force_rport(); fix_contact(); }; if (method=="INVITE") { t_on_reply("1"); }; if (is_uri_host_local()) { # join with next if? if (!lookup("location")) { sl_send_reply("404", "User not found"); break; }; }; if (method=="INVITE" || method=="ACK") { use_media_proxy(); }; if (!t_relay()) { if (method=="INVITE" || method=="ACK") { end_media_session(); }; sl_reply_error(); }; } failure_route[1] { end_media_session(); } onreply_route[1] { if (status=~"(183)|(2[0-9][0-9])") { if (client_nat_test("1")) { fix_contact(); }; use_media_proxy(); }; } Any ideas?.Can this problem be solved? Thanks in advance.