Cannot call 'start' of undefined when starting backbone.js history.

Question

I get Cannot call \'start\' of undefined when calling...

    Backbone.history.start()

When running some checks Backbone return

Answer 1

(function($) {

    var Demo = Backbone.Router.extend({
        routes:{
            '*actions':'defaultRoute'
        },
        defaultRoute:function(action){
            alert('xss');
        }
    });

    var demo = new Demo;
    Backbone.history.start();
    //My site http://bbs.w3hacker.com

})(jQuery);