Error when starting NFS services: "WARNING: Error running install command for sunrpc"

Issue

• The following errors occur when starting NFS-related services:

# service nfslock restart
Stopping NFS statd:                                        [  OK  ]
sh: -c: line 0: syntax error near unexpected token `;'
sh: -c: line 0: `/sbin/modprobe --first-time --ignore-install sunrpc && { /bin/mount -t rpc_pipefs sunrpc /var/lib/nfs/rpc_pipefs > /dev/null 2>&1; ; /sbin/sysctl -w sunrpc.tcp_slot_table_entries=128; }'
WARNING: Error running install command for sunrpc
FATAL: Error inserting lockd (/lib/modules/2.6.18-308.8.1.el5/kernel/fs/lockd/lockd.ko): Unknown symbol in module, or unknown parameter (see dmesg)

• NFS mounts cannot be mounted:

# mount -a
mount.nfs: No such device