[Serusers] Ser + Windows NAT

Hi all, I'm getting a problem when a user behind a windows gateway (NATed client) connects to my ser box. I think this was already discussed here but I didn't find anything on the logs. The problem is with the '407 Proxy Authentication Required' signal that never reaches the client. Here is the scenario: 1- The user sends the INVITE from a higher port to the SIP server. It looks like this: User:63040 -> SER:5060 2- SER responds with a 407 Proxy Authentication Required on the client's local sip port: SER:5060 -> User:5060 At this point, I think windows drops the package because it don't refer to any entry at the NAT table, but I'm not sure about that. I want to know if there's a solution to this 'problem'. Thank you all. -- Thomas Storino Britis TCNet Informatica e Telecomunicacoes LTDA