If you use chkfontpath to delete all of the directories
in the font path, and then try to add a directory, it does
not add the directory. This is with version 1.7-2 (which
I just upgraded to).
An earlier version, under the same test, would add the directory
to /etc/X11/fs/config but fail to precede it with "catalogue =",
which resulted in the directory not being recognized.
fixed in version 1.8, available soon in rawhide.