Have a Merlin Magix v3 (site1) curently networked to 2 other Magix over T1 cards. Have another site with Partner system connecting over Multi-Tech VoIP boxes. Another 2 sites are currently connecting using MCK VoIP boxes to Merlin system phones. These 2 sites are getting replaced with there own self contained systems. Partner systems and Multi-Tech boxes can be implemented and we know this will work; however, a CallManager Express system is being looked at because there will already be 3845 CME bundled routers installed at both sites and probably at site1 as well. The main issue to confirm is that 4 or 5 digit dialing can still be done. Thoughts???