[Serusers] Rewriting URI

I'm trying to forward to a VOIP gateway hosted by Nikotel. They are keying on the @domain in the to-uri. I cannot get the to-uri to rewrite to their domain. What is the trick? I just got off the phone with someone at Nikotel and they said that iptel is working with their gateway. Another similar question. My setup works by: 1) My customer sends an invite for 9725551212(a)mydomain.com 2) I authenticate with my customer with www-authorize 3) I forward the packet using least cost routing, normally to an external sip gateway. Hoever, the SIP INVITE request that I'm forwarding has become polluted with my authentication with my customer. Is there some way to remove that authentication from the INVITE before relaying to SIP PSTN gateway? 4) Is there someway to change the To: uri to be 9725551212(a)SIPGATEWAY.com??? ---greg Greg Fausak