On RH 6.1, a system with the NFS server installed does not
run mountd. This was "automatic" with RH 6.0.
It's a change in policy.
You can set it up to start automatically using:
chkconfig --level 345 nfs on
or by using ntsysv (or another runlevel editor.)
Give me one reason I would want to install the NFS server but not run
One of the most reported causes of security breakins is users
installing everything, and then they have large numbers of
servers running that they don't know what they're for, or how
to configure them sanely.
If the user knows enough to configure the server, the one step
extra to enable it shouldn't be too bad.