[Dovecot] Can Dovecot work with an RDBMS for mail/attachment storage?

This may seem off the wall, but can dovecot be configured to support a connection to a database server and use the database server to store the e-mail message and its attachments?

While you can use Postgres and MySQL for storing and authenticating users, there is a possibility to use an RDBMs to control the mail itself.

Thoughts?

Michael Segel Principal MSCC