Rescue'ing UnknownAction

Rails
1

My rescue_action_in_public works fine catching
ActiveRecord::RecordNotFound errors, but when I try to catch
ActionController::UnknownAction I get the following error display:

uninitialized constant UnknownAction

/usr/local/lib/ruby/gems/1.8/gems/activesupport-1.3.1/lib/active_support/dependencies.rb:123:in
const_missing' #{RAILS_ROOT}/app/controllers/application.rb:233:inrescue_action_in_public’
/usr/local/bin/mongrel_rails:18

This error occured while loading the following files:
action_web_service/dispatcher/action_controller/unknown_action.rb

and my rescue method:

def rescue_action_in_public(e)
	case e
		when ActiveRecord::RecordNotFound, ActionController::UnknownAction
			render :file => "#{RAILS_ROOT}/public/404.html",
			:status => 404
		else
			render :file => "#{RAILS_ROOT}/public/500.html",
			:status => 500
	end
end