Hello, We've had a small but growing number of customers or leads with Shoretel/Mitel phone systems that want SIP trunking, but when we begin trying to setup and test trunking, we're being told they can't configure how the SIP trunking behaves, and that for the vendor to get support, the ITSP needs to be signed up for their Center of Excellence and qualify our SIP trunking with them. One customer says they are using a "MiVoice Business vMCD or 3300 with a MBG Proxy server in server-gateway", the other a "MiVC_Connect_Build_21.90.4127.0". I'm told a couple others are using ShoreTel phone systems, but I haven't seen details for those yet. We're mostly just using Broadworks for SIP trunking, and we've provided SIP trunking for Mitel systems in the past. Does anyone have experience with continuing to make these systems work with generic SIP trunking, or experiences like I've described above? Thanks, -- Nelson Hicks Network Operations SOCKET (573) 817-0000 ext. 210 nelsonh at socket.net