[Serusers] SER has problems matching ACKs to replies

Folks, I found that in the stateful mode, SER is having troubles matching ACKs to negative replies when Vovida B2BUA (1.5.0) is used as one UA, while Cisco ATA 186 as another one. Following is a dump of the session illustrating the problem. As you can see, SER keeps retransmiting 480, despite receiving properly formed ACKs. Does anybody have any ideas what the problem might be? -Maxim P.S. I am also seeing in the logs the following warnings: Apr 7 12:05:28 demo ser[86090]: WARNING: sip_msg_cloner: header body ignored: 4096 B2BUA->SER INVITE sip:16045215277@demo.portaone.com:5060;transport=udp;user=phone SIP/2.0 Via: SIP/2.0/UDP 64.180.102.72:5061 To: <sip:121@64.180.102.72;user=phone> From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 Call-ID: 3135130751(a)192.168.1.20 cisco-GUID: 200546447-2237180178-1764455078-2518034476 CSeq: 2 INVITE Max-Forwards: 10 Expires: 300 Contact: <sip:380442466396@64.180.102.72:5061;user=phone> User-Agent: PortaSIP (030401b) Content-Type: application/sdp Content-Length: 309 o=380442466396 20916528 20916528 IN IP4 192.168.1.20 s=ATA186 Call c=IN IP4 193.111.9.226 t=0 0 m=audio 14000 RTP/AVP 4 8 0 101 a=rtpmap:4 G723/8000/1 a=rtpmap:8 PCMA/8000/1 a=rtpmap:0 PCMU/8000/1 a=rtpmap:101 telephone-event/8000 a=fmtp:101 0-15 a=direction:active a=oldmediaip:192.168.1.20 SER->B2BUA SIP/2.0 100 trying -- your call is important to us Via: SIP/2.0/UDP 64.180.102.72:5061 To: <sip:121@64.180.102.72;user=phone> From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 Call-ID: 3135130751(a)192.168.1.20 CSeq: 2 INVITE Server: Sip EXpress router (0.8.10 (i386/freebsd)) Content-Length: 0 SER->ATA INVITE sip:16045215277@172.17.1.127:5060;user=phone;transport=udp SIP/2.0 Record-Route: <sip:16045215277@64.180.102.72;branch=0> Via: SIP/2.0/UDP 64.180.102.72;branch=z9hG4bK56f9.3c3c97acad0bdb329284be13e26ccc54.0 Via: SIP/2.0/UDP 64.180.102.72:5061 To: <sip:121@64.180.102.72;user=phone> From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 Call-ID: 3135130751(a)192.168.1.20 cisco-GUID: 200546447-2237180178-1764455078-2518034476 CSeq: 2 INVITE Max-Forwards: 9 Expires: 300 Contact: <sip:380442466396@64.180.102.72:5061;user=phone> User-Agent: PortaSIP (030401b) Content-Type: application/sdp Content-Length: 309 o=380442466396 20916528 20916528 IN IP4 192.168.1.20 s=ATA186 Call c=IN IP4 193.111.9.226 t=0 0 m=audio 14000 RTP/AVP 4 8 0 101 a=rtpmap:4 G723/8000/1 a=rtpmap:8 PCMA/8000/1 a=rtpmap:0 PCMU/8000/1 a=rtpmap:101 telephone-event/8000 a=fmtp:101 0-15 a=direction:active a=oldmediaip:192.168.1.20 ATA->SER SIP/2.0 100 Trying Via: SIP/2.0/UDP 64.180.102.72;branch=z9hG4bK56f9.3c3c97acad0bdb329284be13e26ccc54.0 Via: SIP/2.0/UDP 64.180.102.72:5061 From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 To: <sip:121@64.180.102.72;user=phone>;tag=2698540533 Call-ID: 3135130751(a)192.168.1.20 CSeq: 2 INVITE Server: Cisco ATA 186 v2.15 ata18x (030401b) Content-Length: 0 ATA->SER SIP/2.0 183 Session Progress Via: SIP/2.0/UDP 64.180.102.72;branch=z9hG4bK56f9.3c3c97acad0bdb329284be13e26ccc54.0 Via: SIP/2.0/UDP 64.180.102.72:5061 From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 To: <sip:121@64.180.102.72;user=phone>;tag=2698540533 Call-ID: 3135130751(a)192.168.1.20 CSeq: 2 INVITE Server: Cisco ATA 186 v2.15 ata18x (030401b) Content-Length: 201 Content-Type: application/sdp o=16045215277 1110 1110 IN IP4 172.17.1.127 s=ATA186 Call c=IN IP4 64.180.102.72 t=0 0 m=audio 10000 RTP/AVP 4 101 a=rtpmap:4 G723/8000/1 a=rtpmap:101 telephone-event/8000 a=fmtp:101 0-15 SER->B2BUA SIP/2.0 183 Session Progress Via: SIP/2.0/UDP 64.180.102.72:5061 From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 To: <sip:121@64.180.102.72;user=phone>;tag=2698540533 Call-ID: 3135130751(a)192.168.1.20 CSeq: 2 INVITE Server: Cisco ATA 186 v2.15 ata18x (030401b) Content-Length: 221 Content-Type: application/sdp o=16045215277 1110 1110 IN IP4 172.17.1.127 s=ATA186 Call c=IN IP4 64.180.102.72 t=0 0 m=audio 10000 RTP/AVP 4 101 a=rtpmap:4 G723/8000/1 a=rtpmap:101 telephone-event/8000 a=fmtp:101 0-15 a=direction:active ATA->SER SIP/2.0 480 Temporarily Not Available Via: SIP/2.0/UDP 64.180.102.72;branch=z9hG4bK56f9.3c3c97acad0bdb329284be13e26ccc54.0 Via: SIP/2.0/UDP 64.180.102.72:5061 From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 To: <sip:121@64.180.102.72;user=phone>;tag=2698540533 Call-ID: 3135130751(a)192.168.1.20 CSeq: 2 INVITE Server: Cisco ATA 186 v2.15 ata18x (030401b) Content-Length: 0 SER->B2BUA SIP/2.0 480 Temporarily Not Available Via: SIP/2.0/UDP 64.180.102.72:5061 From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 To: <sip:121@64.180.102.72;user=phone>;tag=2698540533 Call-ID: 3135130751(a)192.168.1.20 CSeq: 2 INVITE Server: Cisco ATA 186 v2.15 ata18x (030401b) Content-Length: 0 B2BUA->SER ACK sip:16045215277@demo.portaone.com:5060;transport=udp;user=phone SIP/2.0 Via: SIP/2.0/UDP 64.180.102.72:5061 To: <sip:121@64.180.102.72;user=phone>;tag=2698540533 From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 Call-ID: 3135130751(a)192.168.1.20 CSeq: 2 ACK Max-Forwards: 70 Content-Length: 0 SER->ATA ACK sip:16045215277@172.17.1.127:5060;user=phone;transport=udp SIP/2.0 Via: SIP/2.0/UDP 64.180.102.72;branch=z9hG4bKbc52.5db2fe1211adfdd0d5db3db6e2295344.0 Via: SIP/2.0/UDP 64.180.102.72:5061 To: <sip:121@64.180.102.72;user=phone>;tag=2698540533 From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 Call-ID: 3135130751(a)192.168.1.20 CSeq: 2 ACK Max-Forwards: 69 Content-Length: 0 SER->B2BUA SIP/2.0 480 Temporarily Not Available Via: SIP/2.0/UDP 64.180.102.72:5061 From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 To: <sip:121@64.180.102.72;user=phone>;tag=2698540533 Call-ID: 3135130751(a)192.168.1.20 CSeq: 2 INVITE Server: Cisco ATA 186 v2.15 ata18x (030401b) Content-Length: 0 B2BUA->SER ACK sip:16045215277@demo.portaone.com:5060;transport=udp;user=phone SIP/2.0 Via: SIP/2.0/UDP 64.180.102.72:5061 To: <sip:121@64.180.102.72;user=phone>;tag=2698540533 From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 Call-ID: 3135130751(a)192.168.1.20 CSeq: 2 ACK Max-Forwards: 70 Content-Length: 0 SER->ATA ACK sip:16045215277@172.17.1.127:5060;user=phone;transport=udp SIP/2.0 Via: SIP/2.0/UDP 64.180.102.72;branch=z9hG4bKbc52.5db2fe1211adfdd0d5db3db6e2295344.0 Via: SIP/2.0/UDP 64.180.102.72:5061 To: <sip:121@64.180.102.72;user=phone>;tag=2698540533 From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 Call-ID: 3135130751(a)192.168.1.20 CSeq: 2 ACK Max-Forwards: 69 Content-Length: 0 SER->B2BUA SIP/2.0 480 Temporarily Not Available Via: SIP/2.0/UDP 64.180.102.72:5061 From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 To: <sip:121@64.180.102.72;user=phone>;tag=2698540533 Call-ID: 3135130751(a)192.168.1.20 CSeq: 2 INVITE Server: Cisco ATA 186 v2.15 ata18x (030401b) Content-Length: 0 B2BUA->SER ACK sip:16045215277@demo.portaone.com:5060;transport=udp;user=phone SIP/2.0 Via: SIP/2.0/UDP 64.180.102.72:5061 To: <sip:121@64.180.102.72;user=phone>;tag=2698540533 From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 Call-ID: 3135130751(a)192.168.1.20 CSeq: 2 ACK Max-Forwards: 70 Content-Length: 0 SER->ATA ACK sip:16045215277@172.17.1.127:5060;user=phone;transport=udp SIP/2.0 Via: SIP/2.0/UDP 64.180.102.72;branch=z9hG4bKbc52.5db2fe1211adfdd0d5db3db6e2295344.0 Via: SIP/2.0/UDP 64.180.102.72:5061 To: <sip:121@64.180.102.72;user=phone>;tag=2698540533 From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 Call-ID: 3135130751(a)192.168.1.20 CSeq: 2 ACK Max-Forwards: 69 Content-Length: 0 [the last 3 repeat until timeout hits]