I spent some time last night toying with Mac On Linux, and I have attached the diff containing the modifications to sheep.c that allowed me to compile this successfully.

I also had to hand massage the /lib/modules/2.6.9-1.640/build/include/asm/setup.h file, but that might be something strange on my end.

The modification that I had to make was..

Changing #include <asm-m68k/setup.h>

to

#include <asm/setup.h>

I dont know what this might break, but I guess I'll find out

The patch for sheep.c is attached in unified diff format. Probably patched from the wrong directory in an entirely wrong way... but maybe it'll help someone.