Look into disklabel -B to install boot blocks, and make sure your
partition table is correct, i.e it has a sensical set of
parameters. When I was setting up my second drive, something hosed the
partition table so that the last partition (The netbsd one, even if
you have no dos partitions) was just fine, but the first three had
gobble-de-gook. Once I cleared that up, eveything seemed fine.
If you can, use NetBSD'd fdisk.

Good Luck, and as always, if you should fail in your mission, the
secretary will disavow knowledge of your actions.
--
Hacksaw