Telecom Labs provides installation services for Trixbox requiring Interfacing with the Norstar MICS 6.1 over T1s. We would be glad to assist anyone requiring such integration. Working with the MICS can be difficult if you have never done it before also watch out for Caller ID issues if you are using E&M signalling. Other potential problems include clock synchronization on the T1. It is usually better for the MICS to be the master and the Asterisk/Trixbox slave. You should also disable ztdummy.