rails 2.0 strangeness. Default layouts not working, methods in application controller not visible

Either my app has some bad config files, or some basic behaviors have
changed without any documentation.

1. Default layouts are not being applied
2. Helper methods in application_helper.rb not visible unless helper
:all is set in the controller.
3. Methods in application controller not visible in other controllers.

These things all worked fine in 1.2.x versions. What could be going on here?

Chris