[GRASS-user] Possible databases for GRASS

[Thorsten]

Hello List, 
how flexible is GRASS with regards to the DB where the GIS-data are
stored? I read in the docs that GRASS can now work with many popular
relational DB systems. But what about an entirely unconventional data
store like an object-oriented database implemented in lisp?
Is it just a question of correct data-types, that might be implemented
in any language or system, or do the programming language and the DB
system play an important role?

In other words, could I have a look at a data format GRASS works
with, define a class in an object-oriented lisp system that reflects
that format, and GRASS will be able to access and work with the data?

cheers
Thorsten