We have a customer using a SIP provider we don't normally work with. Issues making calls outbound. The SIP debug has the providers public IP in both the FROM and TO field of the SIP header. The provider claims it will not work like that, has to be our customer's public IP in the FROM field. I compared the debug to our own in-house SIP trunks. The behavior is the same - the SIP debug has the provider's public IP in both the FROM and TO field and it works fine - different SIP provider though. I have manipulated the P-asserted Identitiy header before for certain customers - but that doesn't appear to affect the FROM field. Is there a way on a 7100 to put the customer's public IP into the FROM field instead of the Providers IP?