function addEvent(obj, evType, fn, useCapture){
	if (obj.addEventListener){
		obj.addEventListener(evType, fn, useCapture);
		return true;
	} else if (obj.attachEvent){
		var r = obj.attachEvent("on"+evType, fn);
		return r;
	} else {
		obj["on"+ evType] = obj["e"+evType+fn];
	}
}

function rmEvent(obj, evType, fn, useCapture){
	if (obj.removeEventListener){
		obj.removeEventListener(evType, fn, useCapture);
		return true;
	} else if (obj.detachEvent){
		var r = obj.detachEvent("on"+evType, fn);
		return r;
	} else {
		obj["on"+ evType] = null;
	}
}