Problem:
Encountered error "permission denied" when mounting from one
machine to another machine over NFS.

Solution:
Check the following:

1)  Make sure that you are a super-user when mounting.

2)  Check on the machine mounting to and make sure that the disk is shared.
You can do so with the "exportfs" command which invokes the share
command to print out a list of all currently shared NFS filesystems. If not
shared, then share it by doing the following:

    a)  for local share:  "share /path"
    b)  for NFS share:  "share -F nfs -o rw=machine-to-mount-from,root=machine-
        to-mount-from /path/you/like/to/share".  For example:

        share -F nfs -o rw=benchley,root=benchley /usr/gds.tigger
http://support.codegear.com/cn/print/35306