Finally found the solution to the disklabel problem
Before I did, I went thru large portions of the netbsd SCSI code
It wasn't very amusing :)
I don't know what was wrong, but using

disklabel -w -r /dev/rsd0d a80

instead of

disklabel -w -r /dev/rsd0c a80 (which it should be)

helped.. I guess maybe the kernels compiled w/ the wrong RAW_PART setting
or something.. *shrug*

Hmm.. time to do some partitioning  :)

Oscar