WINE stands for WINE Is Not an Emulator; it only runs on x86 hardware.
Darwine is more ambitious, it aims to port the WINE Windows libraries to the PowerPC API (the Mac\'s \"native language\"), then integrate the QEMU Windows/PPC binary translator into WINE (making, amusingly, the name WINE inappropriate). But Darwine\'s nowhere near done, and if/when it does get done it\'ll be... well, a Really Big Deal.
Along similar lines, Virtual PC actually does make an attempt to run Planeshift, but because VPC 6 can\'t use your Mac graphics card for 3D acceleration, it\'s slower than balls. Maybe on a machine faster than my 1.2Ghz G4 it would work; under Win2K in Virtual PC I couldn\'t get past character creation.