function parseNav() {
	var pageUrlArray = new Array();
	var myArr = new Array();
	pageUrlArray = window.location.pathname.split("/");
	myArr = pageUrlArray[1].split("_");
	temp_item = myArr[0].split(".");
	nav_item = "nav_" + temp_item[0];

	if(document.getElementById(nav_item) != null){
		current = document.getElementById(nav_item);
		current.className +=" nav_active";
		clearInterval(_t);
	}
}

_t = setInterval("parseNav()", 250);