Devise, scoped models

My app accesses multiple databases and I want to scope the model folder. So I would have two users types, e.g. (DB1::User, and DB2::User). I added the routes as devise_for 'db1/user and devise_for 'db2/user'; and I added authenticate_db1_user on the controller. However, I keep getting a failure where Warden is trying to find the model User which of course does not exist.

Is this doable in Devise?