I was wondering over Eileens blog and came to this one - Configuring your PBX for Exchange 2007 - it talks about a preview of documentation covering VoIP gateways, PBXs and gateway. Have a look at the blog and link for more info. Just as a btw, the list is quite extensive: The following PBXs are supported by the Dialogic NetStructure PBX-IP Media Gateway (PIMG). PBX manufacturer PBX Model/Type PIMG model and additional signaling Avaya Definity G3 S8100, S8300, S8700, & S8710 (Communications Mgr SW V2.0 or later versions) PIMG80DNIV4 Avaya Magix PIMG80DNIV4 Mitel SX-200D, SX-200 Light, SX-2000 Light, SX-2000 S, SX-2000 VS, SX-200 ICP PIMG80MTLDNIV4 Nortel Meridian 1 - Option 11, 21, 21A, 51, 61, 71, and 81, Meridian SL1 - Generic X11, Release 15 or later versions, Nortel Communication Server - 1000M, 1000S, 1000E with Rls V3.0 or later versions PIMG80DNIV4 Nortel SL 100 PIMG80LSV4 Analog connectivity using SMDI serial protocol NEC 2000, 2400, 2400 IPX PIMG80DNIV4 Siemens HiCom 300E CS PIMG80DNIV4 Siemens HiCom...