Technically, it doesn't support 68060 processors, PCI buses, and other goodies either. But I imagine adding multi-processor support would require replacing so much of the kernel that you may as well re-write it. But wait. . . . PPC software runs in a separate subsystem anyway, right? Why not just fudge the PPC side of the task scheduler a bit and support multiple processors? Or support hyper-threaded execution via a custom library?
Trev