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 
    {
        alert("Event Handler could not be attached");
    }
}
function removeEvent(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 
    {
        alert("Event Handler could not be removed");
    }
}