JSBinding problem

Hi,
I compiled project, which written in js… And I want bind some classes to native (C++) code…
I generate with bindings-generator CustomClass as said in tutorial:
http://www.cocos2d-x.org/wiki/Binding_Custom_Class_To_Js_Runtime

Problem is how and where I must use this chunk of code in tutorial:

   var customClass = cc.CustomClass.create();
    var msg = customClass.helloMsg()
    cc.log("customClass's msg is : " + msg)

???

I tried it to add in my GameController.js class before the compilation, but it doesn’t work:
jsb-default/src/project.js line:1 msg:TypeError: cc.CustomClass is undefined

Am I using it right or there is other way of binding js to native?