/**
 * X-browser event handler attachment and detachment
 *
 * @argument obj - the object to attach event to
 * @argument evType - name of the event - DONT ADD "on", pass only "mouseover", etc
 * @argument fn - function to call
 */
function addEvent(obj, evType, fn){
 if (obj.addEventListener){
    obj.addEventListener(evType, fn, true);
    return true;
 } else if (obj.attachEvent){
    var r = obj.attachEvent("on"+evType, fn);
    return r;
 } else {
    return false;
 }
}
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("Handler could not be removed");
  }
}

/**
 * Code below taken from - http://www.evolt.org/article/document_body_doctype_switching_and_more/17/30655/
 *
 * Modified 4/22/04 to work with Opera/Moz (by webmaster at subimage dot com)
 *
 * Gets the full width/height because it's different for most browsers.
 */
function getViewportHeight() {
//	if (window.innerHeight!=window.undefined) return window.innerHeight;
	if (top.document.compatMode=='CSS1Compat') return top.document.documentElement.clientHeight;
	if (top.document.body) return top.document.body.clientHeight; 
	return window.undefined; 
}
function getViewportWidth() {
//	if (window.innerWidth!=window.undefined) return window.innerWidth; 
	if (top.document.compatMode=='CSS1Compat') return top.document.documentElement.clientWidth; 
	if (top.document.body) return top.document.body.clientWidth; 
	return window.undefined; 
}