function nav_check() {
	    	if (!document.getElementsByTagName){
    	    	return;
    		}
    		var u_list;
    		var pattern = 'nav_';
    		var all_uls = document.getElementsByTagName('ul');
    		for (var i=0; i<all_uls.length; i++){
        		u_list = all_uls[i];
				list_size = u_list.childNodes.length;
				if (list_size <= 1) {
					u_list.className = "none";
				}
        	}

		}
		window.onload = nav_check;