Using Countries (Location module) as Taxonomy Tags (Category module)

Howdy,

i am trying to set up a site where nodes submitted by users are localized with the Location module, and sorted by country/state/city with the Category module.

Is there a way to prevent users to choose the same Country, State, City two times (one for the Location module and one for the Category module)?

I have been looking around all the morning on Drupal.org for a way to joint Taxonomy(Category) and Location modules togheter, so that country/state selection in the location module is reflected as a term (category) to tag nodes, or viceversa.

This looks like a missing feature also other people are looking for, and is desirable mainly because it would permit:
1. filter and/or search tagged nodes by countries/states/cities
2. display contry/state tags in nodes
3. submit countries/states main pages

Some usefull links i found:
. http://nicklewis.smartcampaigns.com/node/722 (code used to automatically generate a taxonomy term from $userCountry)
. http://drupal.org/node/48843 (Drop Down Box Dynamically Filled With Taxonomy)
. http://drupal.org/node/17762 (Pulldown top level category links)

And other drupalers asking similar features (still without a solution):
. http://drupal.org/node/33282
. http://drupal.org/node/51478
. http://drupal.org/node/40211

lot of respect to anyone who can solve this tricky issue ;)

marco