Serious Bug in Rails 2.2 using method "_ids" ...?

Hey Guys,

considering the following Model:

class User < ActiveRecord::Base
has_many :posts, :include => [:comments, :ratings], :dependent =>
:destroy
end

This code will raise an ActiveRecord::MissingAttributeError Exception
(comment_id is missing):
@user.post_ids

Can anyone confirm this or does someone have an idea whats going wrong
here? Using Rails 2.2.2

Cheers.

oops. This was supposed to go into Rails Forum.