How can I stop OS X from automatically connecting to an NFS server on startup?

I upgraded to Lion today, but was having the same problem on Snow Leopard. When I start up my Mac and login, it automatically connects to an NFS server. I know this because I see the server in Finder in the Shared section. I'm assuming I connected to the server at some point in the past, but I'm not sure how to make it stop connecting now. Where can I look? Even after ejecting the server, it reconnects on the next startup. What can I do to make it stop?

Further information - here's what my /etc/auto_home looks like:

#
# Automounter map for /home
#
+auto_home  # Use directory service
#
# Get /home records synthesized from user records
#
+/usr/libexec/od_user_homes

And running /usr/libexec/od_user_homes produced no output.

The mount doesn't show up in Disk Utility or the Directory Utility, and running lsof doesn't show the mount (/CIFS). df does show /CIFS and indicates that the Filesystem is x-browser:

Here's /etc/auto_master:

#
# Automounter master map
#
+auto_master        # Use directory service
/net            -hosts      -nobrowse,hidefromfinder,nosuid
/home           auto_home   -nobrowse,hidefromfinder
/Network/Servers    -fstab
/-          -static

And the output from mount:

/dev/disk0s2 on / (hfs, local, journaled)
devfs on /dev (devfs, local, nobrowse)
map -hosts on /net (autofs, nosuid, automounted, nobrowse)
map auto_home on /home (autofs, automounted, nobrowse)
x-browser: on /CIFS (nfs)
localhost:/gWMIVnK_1WG9ZzUq0q3qb7 on /Volumes/MobileBackups (mtmfs, nosuid, read-only, nobrowse)

I had the same problem with CIFS-mount, x-browser… That happened because I tried Sharity 3 and 'deleted' it by putting the icon in the trash, like Mac users usually do. :) But the program was still installed and put the CIFS icon on the Desktop every day.

I solved it using the following Terminal command:

sudo /Library/StartupItems/Sharity3/uninstall

You may want to consider using the NFS Manager application to help you locate and disable the NFS automount. You should refer to this section of the manual for assistance.

The mount name /CIFS and the lack of NFS information indicates you may be running Sharity. Check if it's installed, using Spotlight. If it is, you can find the documentation here.

NFS mounts should show up in Disk Utility. Open Disk Utility.app (In /Applications/Utilities/) and under the File menu select NFS Mounts. Select the URL of the drive that keeps showing up and click the minus button on the lower left corner of the screen to remove it.

Check your start up items in system preferences. It might be in there which would be why it keeps auto mounting.