function changeClass(current_li) {
	var obj = current_li.ancestors()[0].childElements();

	for (var i=0; i < obj.length; i++) {
		if (obj[i].className.search("current") > -1) {
			obj[i].className = obj[i].className.replace("current", "inactive");
		} else if (obj[i].className == current_li) {
			obj[i].className = obj[i].className.replace("inactive", "current");
		}
	}
	current_li.className = "current";
}