Thanks heaps for your replys!

Yes I have built devices and forced a fstab build. The mini
shell in the installer finds the fs you can cd though it no
problem. Just the kenal wont mount it.
this is my fstab:

   /dev/sd1a / ffs rw 1 1
   /dev/sd1b none swap sw 0 0
   kern /kern kernfs rw 0 0
   proc /proc procfs rw 0 0

any other ideas?
thanks heaps for you help

Carl