Merging Admin Dirs?

["Christian Goetze (CG Linden)" <cg@lindenlab.com>]

Apologies in advance if this is the inappropriate list, please feel free
to refer me to a better place.

I am aware that there is a dpkg --admindir=<someplace> option, and I
wish to use it for doing installs "on top" of a canned debian install.
The idea is to allow two separate groups of maintainers to control what
is installed on a specific box: the core group which produces the base
install, and an application group which adds rapidly changing versions
of applications on top of the core install.

I wished there was a way to specify multiple admindirs, only one of
which is used to write the new information, but all of them are used to
resolve dependencies. My current choices seem to be:

    * Use --admindir on an initially empty directory, and don't check
      for system dependencies, assume they are OK - one can do a dry run
      install without --admindir to verify that these are satisfied
    * Use --admindir on a directory that contains a copy of the "core"
      admin dir. This will work until the core is updated, after which
      there is no way to go anymore.
    * Don't use --admindir, share the system dir. This would require
      changing the way our core group maintains our server farm -
      currently maintained via rdist...

Ideas?
--
cg