Problem booting miniroot 1.6B

Hi
 I tried booting my hp425s with the new miniroot.gz (200207100000) produced
from releng.netbsd.org

Now, correct me if I am wrong, but I should be able to do a

dd if=miniroot.fs of=/dev/rsdxb

and then be able to boot from there, correct?

At the bootloader, however, when I specified the netbsd file on the swap
partition, I would receive a

"inappropriate file type".

If I tried booting a file that I knew did not exist, (for instance, coco), I
got an file not found . So this means it finds the file, just does not know
what to do with it.

note: These messages appear to come from the second stage bootloader, from
the current 1.5 installed on the box. Would it be accurate that this will
also have to be upgraded to a 1.6 version?

Thanks

Chris