Multistore with own database

Would it be possible to set up a multistore where each store (subdomain) would have it's own database?

I would love to be able to install opencart just once on my webserver, then have multiple subdomains as stores and each store having it's own database. This way I have full flexibility and a subuser who is logging in would only see it's own products/categories/settings.

this: http://www.opencart.com/index.php?route ... on_id=5213

would come about as close as you can get, the databases aren't separated, but users can only see their own products /etc.