user.rb

  def self.find_by_email(email)
    User.new :email => email
    if engine_user = EngineUser.find_by_email(email)
      return find_by_engine_user_id(engine_user.id)
    end
  end

  def self.find_by_email!(email)
    engine_user = self.find_by_email(email)
    raise ActiveRecord::RecordNotFound unless engine_user 
    engine_user
  end