[Users] BYE retransmits too quick!

I'm doing an interop test with a well known ITPS, they are kicking back these BYE retransmits, like: SIP MESSAGE 18 216.138.115.30:5061(www.testnode-3.com) -> 209.247.16.2:5060(deneps551.Denver1) UDP Frame 18 17/Feb/06 17:09:36.8142 TimeFromPreviousSipFrame=0.0010 TimeFromStart=8.0692 BYE sip:209.247.16.2:5060 SIP/2.0 Record-Route: <sip:216.138.115.30:5061;ftag=245-192.168.10.1;lr> Record-Route: <sip:216.138.115.27;ftag=245-192.168.10.1;lr> Via: SIP/2.0/UDP 216.138.115.30:5061;branch=z9hG4bK036d.a99621d6.0 Via: SIP/2.0/UDP 216.138.115.27;branch=z9hG4bK036d.1fe4ca41.0 Via: SIP/2.0/UDP 198.41.9.65:5060;branch=z9hG4bK245-192.168.10.1.256 Via: SIP/2.0/UDP 192.168.10.23:5060;branch=z9hG4bK1371-192.168.10.23.1374 From: <sip:+18663072489@216.138.115.30:5061>;tag=245-192.168.10.1 To: "Unknown" <sip:+17205626376@209.247.16.2>;tag=VPSF50603522629634 Call-ID: DEN05020060217230928060500(a)209.244.48.214 CSeq: 101 BYE Max-Forwards: 67 Record-Route: <sip:198.41.9.65:5060> Contact: "8663072489" <sip:+18663072489@198.41.9.65:1074> SIP MESSAGE 19 216.138.115.30:5061(www.testnode-3.com) -> 209.247.16.2:5060(deneps551.Denver1) UDP Frame 19 17/Feb/06 17:09:36.8424 TimeFromPreviousSipFrame=0.0282 TimeFromStart=8.0974 BYE sip:209.247.16.2:5060 SIP/2.0 Record-Route: <sip:216.138.115.30:5061;ftag=245-192.168.10.1;lr> Record-Route: <sip:216.138.115.27;ftag=245-192.168.10.1;lr> Via: SIP/2.0/UDP 216.138.115.30:5061;branch=z9hG4bK036d.a99621d6.0 Via: SIP/2.0/UDP 216.138.115.27;branch=z9hG4bK036d.1fe4ca41.0 Via: SIP/2.0/UDP 198.41.9.65:5060;branch=z9hG4bK245-192.168.10.1.256 Via: SIP/2.0/UDP 192.168.10.23:5060;branch=z9hG4bK1371-192.168.10.23.1374 From: <sip:+18663072489@216.138.115.30:5061>;tag=245-192.168.10.1 To: "Unknown" <sip:+17205626376@209.247.16.2>;tag=VPSF50603522629634 Call-ID: DEN05020060217230928060500(a)209.244.48.214 CSeq: 101 BYE Max-Forwards: 67 Record-Route: <sip:198.41.9.65:5060> Contact: "8663072489" <sip:+18663072489@198.41.9.65:1074> Why is the BYE being sent so quickly? This is an intermediate UAS proxy, and every now and then it spits out an extra BYE like this. Shouldn't this wait 500ms before doing a retry? The rest of the trace is clean. I can forward the whole thing if there is any interest. -g -- Greg Fausak greg(a)thursday.com