I am trying to solve how to have varying metadata sets for different
functional areas within one portal. We are using a modified Dublin
core metadata strategy, and need to show different controlled
vocabulary depending on the functional area.

1) We have site definitions for level 1, 2 and 3 of the portal
site and based on these site definitions we have already created the
areas and sub areas accordingly.

2) We have around 500-600 areas that are using these site
definitions.

3) Based on these site definitions files, the document
libraries have been created in the respective area and the Meta data
properties and values are showing up as they have been defined in
the schema.xml under the doclib folder for the respective site
definitions.

4) At this if we want some new value to be added to the
schema, we can surely modify the schema.xml and then the same would
show up on all the areas that use these site definitions.

5) We have 10-12 business units and each of these business
units now require different values to show up in the combo boxes
when a document is uploaded in the document library. If we update
the schema.xml all the business units will see the same values which
we don't want.

6) Is there some way to apply a document library schema
template to each of these business units now that they have been
already created?