The ez430 RF2500 port of the Contiki OS was created as the entry to the MSP430 Design Contest. Currently the port allows to use one RF2500 board as a terminal and another RF2500 board as a sensor node. For further development your may check out the source code from the repository of Contikiprojects. More precisely, the code of the project is here and the documentation is here.

Alternatively, you may download the code and the documentation from this very website.