Include jquery-rails into Engine (Rails 3.x)

engine.rb

require 'rails'
require 'jquery-rails'

$:.unshift File.dirname(__FILE__)
module MyEngine
  class Engine < Rails::Engine
    
    if defined?(query::Rails::Engine)
      initializer :after_append_asset_paths,
                  :group => :all,
                  :after => :append_assets_path do
         config.paths.add File.join(::Jquery::Rails::Engine.root.to_s, "vendor", "assets", "javascripts").to_s, :glob => "*"
      end
    end

  end
end