sunrpc ref count leaks in nfs

On a freshly installed RedHat 6.1 (2.6.32-131), I have sunrpc loaded with a reference counter = 1, it is for the mount of sunrpc on /var/lib/nfs/rpc_pipefs.

If I want, I can unmout it and unload sunrpc.

If I execute a "service nfs start" and then a "service nfs stop" (and I unmount /proc/fs/nfsd, I execute "service rpcidmapd stop", I remove nfsd, lockd, nfs_acl, auth_rpcgss, exportfs, then "service rpcbind stop", "service nfslock stop") then I am left with the reference counter of sunrpc = 4. I.e. once used NFS, I cannot unload sunrpc.

Have you got a correction for this, please?

Thanks,

Zoltan Menyhart