Bottom Up ORM / scaffolding

Hi,
I am a total newbie to ruby on rails, but have been investigating it
and ruby and ruby on rails seem to have a LOT of things i really like
about a programming language.. liked most of it.. except 1 thing..

And that is ruby on rails scaffolding, it build up ur basic model view
controller from the database! I really dont like that..

I am the kind of developer that likes to design his application object
oriented (UML), and base the application on that.. not on the database
that i derive from the object model..

By building ruby objects bottom up from the database i loose all kinds
of things, like generalization, association classes, interfaces...

Probably this can all be re-adjusted after scaffolding, but im looking
for the perfect language to sink my head in.. with everything i like..
possibly build my career on it.

Can somebody tell me if i am right about what im saying about ruby on
rails scaffolding or not?

Regards,
Klaas