Cookie control for Joomla! administrator area

index.php

<?php
define('_JEXEC', 1);
$admin_cookie_code="CODE_HERE";
//setcookie("AdminSession",$admin_cookie_code,0,"/"); $_SERVER['HTTP_HOST']
setcookie("AdminSession", $admin_cookie_code, 0,"/administrator/", $_SERVER['HTTP_HOST'], false);
header("Location: ../administrator/index.php");

//administrator/index.php
if (!isset($_COOKIE['AdminSession']) or $_COOKIE['AdminSession']!='213')
{
	header("Location: ../index.php");
}