Hey... I'm using Flash a lot and my classes uses EventDispatcher class which allowes me to define custom events of a class. How can I do this in javascript.

I would like to do something like this:

var MyClass = function() {
};
MyClass.prototype = {
  test : function() {
    dispatchEvent('ON_TEST');
  }
};

var mc = new MyClass();
mc.addEventListener('ON_TEST', handler);
function handler() { alert('working...') }

How is this posible with Javascript?