Prevent /u from showing up on users desktops in F7

[Darryl]

How do I prevent filesystems/folders from showing up on user's gnome 
desktops? I have /u being mounted out of /etc/fstab at boot time but do 
not want it on the user desktop. Other filesystems such as /var and 
/boot are somehow excluded so there must be some kind of configuration 
file to adjust this behavior but I can't seem to locate it :-(.