Hi, I have some 7960 phones all behind Firewalls. I came up with a semi-elligent DynamicDNS hack to solve NAT problems, but it had a variety of problems - I'm now looking at using the 7960 command: nat_received_processing: 1 Any one with any experience using it? According the Admin manual for the 7960: Use 0 to disable NAT received processing and 1 to enable NAT received processing. Default is 0. If nat_received_processing is enabled, and received= tag is in the Via header of the 200 OK response from a REGISTER, the IP address in the received= tag is used instead of the nat_address in the Contact header. If this switch occurs, the phone unregisters the old IP address and reregisters with the new IP address. I have this enabled, and I can see the received= flag SER is sending back upon registration, but the 7960 seems to totally ignore it? Any ideas? Sean Watkins