Uninitialized constant helper constant?

Hi there,

I am getting a weird exception when creating a new controller
‘SimpleRSS’ and pointing my browser to a correct route like
http://rails/simple_rss/last_added, the exception is the following :

uninitialized constant SimpleRssHelper

This error occured while loading the following files:
C:/Dev/rails/annotea/working_copy/trunk/annotea/public/…/config/…/app/controllers/simple_rss_controller.rb

Bests,

Sergi
Borràs