function addEvent(obj, evType, fn, useCapture){
	//check for Moz addEventListene
	if (obj.addEventListener){
		obj.addEventListener(evType, fn, useCapture);
		return true;
	//otherwise must be IE
	} else if (obj.attachEvent){
		//prepend 'on' to event type handler
		var r = obj.attachEvent("on"+evType, fn);
		return r;
	} else {
		alert("Handler could not be attached");
	}
}