this worked in Rails2 RefineryCMS -- in the initializers folder

page_extensions.rb

class Page
  acts_as_commentable
  
  has_many :page_widget_assignments
  has_many :assigned_widgets, :through => :page_widget_assignments, :source => :widget

  def widgets
    if assigned_widgets.blank?
      parent_id? ? parent.widgets : Widget.system
    else
      assigned_widgets
    end
  end
  
  def body
    return self[:body]
  end
end