Remote mounts also need the nfsd daemon to execute on NFS servers. Check the server's file /etc/init.d/nfs for the following (or similar) lines:
if [ -x /usr/lib/nfs/nfsd ] then $TFADMIN /usr/lib/nfs/nfsd -a > /dev/console 2>&1 fiTo enable this daemon without rebooting, log in as the network administrator (or as a privileged user) and type: