I tried to mount a nfs share over ssh :

ssh -f -L${NFSPORT}:${IPSERVER}:2049
-L${NFSMOUNTPORT}:${IPSERVER}:32767 -l root ${IPSERVER} sleep 60
mount -t nfs -o
tcp,sync,rsize=8192,wsize=8192,soft,timeo=60,port= $NFSPORT,mountport=$NFSMOUNTPORT

The ports opened are 22 (ssh) and 111 (portmap).

When i try the mount command, i obtain this error message :
mount to NFS server 'localhost' failed: possible invalid protocol.

What could be the reason of this error message?