RAID5 3x 3TB SATA drives, help!

[Glenn Richards <glenn%squirrelsolutions.co.uk@localhost>]

I cannot get this to work!

Using NetBSD 6.0.1/amd64 with 3x 3TB SATA disks as RAID5, booting from a 
CF card.

I've set up a dk partition on all 3 disks, set the RAID up on dk0, 1 and 
2, created a new dk3 device on the RAID. All works so far but I'm unable 
to mount dk3 as the root file system; it seems that NetBSD doesn't 
support autoconfigure of a dk file system, unless there's something I've 
missed?

Have googled and found this:

http://mail-index.netbsd.org/netbsd-users/2012/07/20/msg011157.html

which seems like someone's having the same problem. Googling is limited 
as it sees the "dk" in the search string and tends to return a whole lot 
of Danish websites...

Is there a HOWTO somewhere on how to do this? Failing that is it 
possible to change the root filesystem "on-the-fly" from wd3a to dk3 
before going multi-user?

Thanks in advance... while I still have some hair left!

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