Home Automation, Inc. (HAI) has released some more details about their soon to be released 'Cellular Communication Center' (Part # 70A00-1).  This looks like a great and easy way of adding redundancy to your alarm panel (no matter what the make/model is), even if it doesn't support cellular interfaces.

"Connects with any HAI Omni or Lumina home control system, as well as any security panel. Checks the status of your home phone line. If the phone line is unavailable, it will emulate the phone line signal, and the panel will dial out using your GSM cellular network to communicate with a central monitoring station, and/or your cellular telephone. Includes backup battery and antenna. Requires GSM SIM card and cellular service. Can also be used in applications where landlines are neither present nor desired."