I am considering doing a project which would provide unified API and tools (import/export, etc.) for object databases (e.g. Caché, Objectivity) for .NET.

It would provide:

• schema generation from CLR classes,
• generation of C# classes from given OODBMs schema,
• API for deleting, creating and updating objects,
• Linq provider,
• API for calling object's methods on DB server,
• some of OODBMs provide some kind of SQL support, so API for this,
• providers for Caché and Objectivity in first phase.

Does any project which implements any of above exist? Can this be achieved with NHibernate dialects? or are OODBMs so different than RDBMs that it worth doing separate framework for them?