platform for mainstream enterprise applications

[Marc Model]

I am a Django newbie.

I expect that Django could be a good platform to build a force.com like application platform: a platform where business experts can define business data models, authorization rules (which user role can access or edit what parts of a model in what state) and workflow rules.

I wander if there are already initiatives out there to build this type of platform, or components of it?

For instance I found on the internet some discussion around dynamic models (classes) exploiting meta-programming facilities of Django. That could be the foundation of such platform.

Thanks for any referral.

Marc