If you choose to mount over NFS just one of your user’s home directories (e.g. /home/jem) under Ubuntu, then you may come accross issues such as failure to log in, the screen freezing (but mouse still moving), loss of configuration data (e.g. icons in your panels), being told that your login session lasted under 10 seconds, and just general instability.
The reason for this is, in Ubuntu’s rush to get you to the Desktop quickly, it loads up GDM (and possibly auto-logs you in) *before* your home directory is mounted over NFS “Network File System (protocol)”). This is a simple issue of priorities. However, if you log in before the home directory has been mounted, then gconfd-2 and other similar apps will load (or save) settings to your (supposedly empty) /home/jem on your hard drive. When you give up and log out (e.g. Control-Alt-Backspace, or a proper logout), and log back in again, these programs will still be accessing the wrong settings, because they continue to run in the background.
The solution is to abort Ubuntu’s Windows-like behaviour of
allowing you to log in before everything has started running at boot
time - change GDMs priority from 14 to 80 (or some other number). I
chose to do this the lazy way, using “
bum”. BUM, the Boot Up Manager,
is a simple way to change all things related to booting. It is easy to
use, though it does take quite a while (a few minutes!) to start the
first time you run it. It must be run in a graphical environment. Simply
tick the advanced box, go to the third tab, find gdm, and change its
priority up to 80. Save, exit and reboot, and all is well again in the
world… though you may have to restore your settings from a backup, or
go through the long process of re-configuring your desktop the way you
like it. Good luck!