Helper all -- not working?

Rails
1

I put a helper into app/helpers/application_helper.rb

module ApplicationHelper
  def foo
  end
end

I have “helper :all” in my application controller

class ApplicationController < ActionController::Base
  helper :all # include all helpers, all the time
  ...
end

But when I try to use the helper from a controller, it does not find it.

The controller is in app/controllers/json/calls_controller.rb and it is
a
subclass of ApplicationController:

module Json
  class CallsController < ApplicationController
  ... use foo
  end
end

There must be something obvious that I’m missing.

I’m on Rails 2.3.11 using Ruby 1.9.1 p378.

Anyone know the errors of my way?

Thank you in advance
pedz