consoles not dying after logout

[Jon Genetti]

System: 210GTX and several PIs running 3.3.1

We are running the automounter to mount user's home directories which
can be on any of 3 servers.  When one of the servers went down the other
day, I noticed that a few of the machines were frozen even though nobody
was logged in.  When I went to investigate I saw that each of these had
at least 1 process like this running:

 joeblow  5898     1  0 14:05:50 console   0:00 -csh

even though that person had logged out hours ago.  Then a df shows:

server1:/485/joeblow    nfs  583680  540672   43008  93%  /tmp_mnt/user/joeblow

his home directory as still being mounted even though it should have timed
out and unmounted.  Has anyone else noticed this or knows why this might
be happening?

thanks,
jon genetti
genetti at cs.tamu.edu