This patch fixes what turned out to be a longstanding problem. 
The exportfs needs to export the root, not the namespace of the 
server. This patch (from Russ) remounts '#s/boot' on /root and
then exports /root. This fix is needed for those users who 
set up combined auth/cpu/fs systems, because the /mnt/factotum
on the auth server collides with the /mnt/factotum on cpu servers
that mount the file server (in the case that auth/cpu/fs are
the same).