Log Message:
Importing databases/ruby-dm-rails package version 1.2.0.

Dm-rails provides the railtie that allows datamapper to hook into rails3 and
thus behave like a rails framework component.  Just like activerecord does in
rails, dm-rails uses the railtie API to hook into rails.  The two are actually
hooked into rails almost identically.

Creating new datamapper apps on rails3 from scratch is actually really easy.
The following will guide you through the process.