All, I am posting this here to announce I have finally managed to get my Cisco IAD2421 to speak MGCP with Asterisk. Due to an acute lack of reading on the subject as searched on Google, I'm putting this out with the hope that it helps whomever should need to do this in the future. This should also apply to the IAD2420 and the other models in the line, but as I do not have access to those, they are untested. I have posted all my configurations and notes made during this effort in the wiki at http://www.voip-info.org/tiki-index.php?page=Asterisk+phone+cisco+iad2420 (I know its not really a 'phone' but it seemed like the most appropriate way to list it.) Working and tested is the ability to call into the automated attendant and receive/process digits, as well as call another IAD channel and hold a conversation. A patch has been submitted at http://bugs.digium.com/bug_view_advanced_page.php?bug_id=0002982 (Asterisk bug ID 0002982) which improves the reliability of the IAD by hanging up calls when the IAD and Asterisk get out of sync. More details are in the bug report. My IAD2421 provides 16 analog pots channels via an Amphenol connector. It speaks MGCP with Asterisk and does minimal (if any) actual call processing internally. It is, however, also a full router with IPsec and SSH (if you have a recent enough version of the IOS and beefy enough hardware). Mine includes 1 Fast Ethernet port, 1 onboard Serial 0, and 1 T-1/PRI WIC. AFAIK, the WIC cannot be used for voice channels (data only). These devices are End Of Lifed as far as I know. Hope this helps! /BAK/