> The next problem is the endienes. i386 is
> low endien ("sysctl hw.byteorder" gives "hw.byteorder = 1234") and AFAIK
> ppc is big endien. ("sysctl hw.byteorder" gives "hw.byteorder = 4321")

This is no problem: you need "options FFS_EI" in your kernel config file,
and when creating the filesystem you have to specify "-B be" on the i386
to force the filesystem into big endian byte order.

The disk label problem is a real problem though, if you are not going to
use the whole disk as a single partition.

Martin