function setClassName(targetObj, targetClassName){
	targetObj.className=targetClassName;
}

function getCurrentPosY(){
	if (document.body && document.body.scrollTop)
		return document.body.scrollTop;
	if (document.documentElement && document.documentElement.scrollTop)
		return document.documentElement.scrollTop;
	if (window.pageYOffset)
		return window.pageYOffset;
	return 0;
}