Prioritizing multiple defaults.list to set default applications for mime types

["John A. Sullivan III" <jsullivan opensourcedevel com>]

Hello, all.  We're having some difficulty properly setting GNOME
defaults using XDG_DATA_DIRS.  In our specific case, we are trying to
set the system default for all users to acroread from Evince because
Evince is not properly rendering some of the more complicated documents.

We set
XDG_DATA_DIRS=/data/.Common/xdg/default:/usr/share:/usr/local/share::/opt/trinity/share/:/usr/share/

/data/.Common/xdg/default has an applications directory with a
defaults.list file setting the default pdf application for
application/pdf and application/vnd.adobe.pdf to AdobeReader.desktop
which points to acroread.

The problem seems to be that there is
a /usr/share/gnome/applications/defaults.list which is a link
to /etc/gnome-vfs-2.0/defaults.list which sets Evince as the default.
This seems to be overriding our defaults.  If I edit that file or rename
it, the default is set properly.  To override it, I tried creating a
gnome directory under /data/.Common/xdg/default/ and moving the
applications directory under that in case gnome is a preferred path for
gnome applications to find their settings.  That did not work.  I tried
putting the Common directory at the end of XDG_DATA_DIRS in case it is
read in the opposite order from what I assumed; that did not work.  So
we see the cause but do not yet have the solution.

How do we get our centralized settings to override those
in /etc/gnome-vfs-2.0/defaults.list so that we don't have to edit every
single one of those files thus defeating the purpose of centralized
administration? Thanks - John

PS - I just realized that I should clarify this is a vserver environment
with a shared file system via mount rbind.  Thus, we can set one xdg
directory for hundreds of vserver guests rather than
editing /etc/gnome-vfs-2.0/defaults.list on each one of those guests.
In a stand alone environment, the highest centralization would
be /etc/gnome-vfs-2.0/defaults.list.  Thanks - John