[Serusers] When will SER send Stop message to Radius Server

Hello List, First, many thanks to those who replied my previous dumb questions. My SER 0.9.0 with mysql auth and radius accounting with mysql is seemingly working ok. I have a question about SER's Radius accounting, but not sure how to ask, here is my situation: I'm testing out calls between XLite (caller) and a hardware phone (callee), but for some reason the call duration is always 30 seconds longer than actual (For both cases, it's the callee who does the hang up). I tried calls between XLite and XLite and the duration would be accurate. So I ngrep-d the traffic for both scenairos, for XLite-XLite's case, the flow is the side who hangs up (say, UA1) will send the BYE to SER then SER relays the BYE to UA2. Then UA2 sends an ACK to SER and SER relays the ACK to UA1. For the XLite to HW phone's case, the phone will still send the BYE to SER and SER will relay it to XLite. However, XLite will not send an ACK to SER. And the phone sends another BYE to SER and then SER relays it to XLite -this is repeated for 5 - 6 times until finally SER will just send a 408 Request Timeout to the HW Phone. And it seems this is the time when SER sends the Stop message to the Radius server, and hence the extra 30-sec call duration. So I'm wondering if SER indeed needs the ACK for the BYE message before sending the accounting stop message to Radius? Or is my situation caused by some other reasons? Thank you in advance. _________________________________________________________________ Is your PC infected? Get a FREE online computer virus scan from McAfee® Security. http://clinic.mcafee.com/clinic/ibuy/campaign.asp?cid=3963