Teach mootools to clone events of children too.

mootools.cloneEventsDeep.js

Native.implement([Element, Window, Document], {
	cloneEventsDeep: function(from, type){
		if (this.getChildren().length > 0) {
			this.getChildren().each(function(item, index) {
				item.cloneEventsDeep(from.getChildren()[index], type);
			});
			this.cloneEvents(from, type);
		} else {
			this.cloneEvents(from, type);
		}
		return this;
	}
});