Since most of the code is just plain Arduino code, it should work on other hardware as well. However, there's two caveats that spring to mind:
- The current code is fairly resource intensive - we use over 140K of flash now and IIRC a significant portion of the 32K of SRAM available. A typical Arduino Uno only has a fraction of that available. It's likely that a lot of stuff can be stripped down to fit, though.
- The wireless mesh code uses Atmel's lightweight mesh framework, which is built directly on top of Atmel's RF hardware. Adapting that for RFM hardware is probably tricky, and might even violate Atmel's license.