We are deploying in a cable environment, and for sake of ease we are registering all SIP UAs by their MAC address. And associating phone numbers with dbaliases. It all works great until we try to send a phone call to the PSTN. I need to know the way to modify the from_uri to change it from the MAC of the device to the actual phone number which we will retrieve using avp or so. Thanks in advance. Kw