function roll_menu(id) {
	var tab_divs=document.getElementById("second_menu").getElementsByTagName("DIV");
	for (var x=0;x<tab_divs.length;x++) {
		tab_divs[x].style.display="none";
	}	
	if (document.getElementById("level2_"+id)) document.getElementById("level2_"+id).style.display="block";
}