[Serusers] Broken "SIP Aware" Router

We have started having problems with customers in BellSouths ADSL network. New customers are being given the Westell ADSL modem which appears to be "SIP Aware". But the implementation is terribly broken. The symptoms are that SIP INVITES cannot penetrate the NAT on the Modem even though we have a permanent Keep-Alive from the inside (every 15 seconds). Furthermore when the customer tries to make a call, the modem changes the source port of every single packet of the dialog. Thus breaking the SIP dialog completely. Our interim solution was to setup these customer on an alternate server listening on a different port. For everybody's reference the modem version is: Westell B9061003006 and the Software is: 03.00.61 I have tried to contact Westell directly but they have not answered. I hope this is not something thats going to start happening with all modem manufacturers or else were going to have loads of trouble. -- Andres Network Admin http://www.telesip.net