Rails 2.2rc2: ArgumentError - Anonymous modules have no name to be referenced by...

If you convert your Rails 2.1 app to Rails 2.2RC2, you'll see this
fancy error message as soon as you start script server:

This SHOULD not happen for 2.2 RC2 because 2.2 already has a separate
branch. And renaming application.rb -> application_controller.rb is an
edge only change.

Ah, ok. My bad. I grabbed trunk instead of RC2