Extending a child of active record oddness

This feels like a newbie question. But, I'm not... I promise... well I hope.

Lower in this mail I've copied in 2 related classes and a module that
extends one of them. This all works fine and calling Image.help
returns "youre screwed" as it should do.

However, if I take out the "include ImageExtension" out of Image and
put it into the child of Image, "ChildImage" (imaginative I know) it
no longer works.. Calling ChildImage.help returns method not defined.
Bah.

I'm totally blaming active record here because it works fine without
it. Ideas anyone?

Cheers
-h

class Image < ActiveRecord::Base
include ImageExtension
end

class ChildImage < Image
end

module ImageExtension
def self.append_features(base)
   super
   base.extend(ClassMethods)
end

module ClassMethods
   def help
     "youre screwed"
   end
end
end

However, if I take out the "include ImageExtension" out of Image and
put it into the child of Image, "ChildImage" (imaginative I know) it
no longer works.. Calling ChildImage.help returns method not defined.
Bah.

I'm totally blaming active record here because it works fine without
it. Ideas anyone?

Just tested in 1.1.6 from script/console, works as it should.

Running on Win XP.

I split it up into two model files and image_extension in lib.
What are you doing to test this?

Max