If the xfs config file (/etc/X11/fs/config) contains an entry like:

catalogue =
      /path/to/font/dir1,
      /path/to/font/dir2,
      /path/to/font/dir3,
      /path/to/font/dir4

then when chkfontpath tries to add /path/to/new/font/dir to this, the
resulting entry is (note the missing comma on the first line):

catalogue = /path/to/new/font/dir
      /path/to/font/dir1,
      /path/to/font/dir2,
      /path/to/font/dir3,
      /path/to/font/dir4

  This one bit me when I upgraded to netscape-common-4.72-6 which runs:

    /usr/sbin/chkfontpath -q -a /usr/X11R6/lib/X11/fonts/75dpi

on install.

  Incidently, are the -q & -a flags to chkfontpath documented anywhere?