PHP: WWW-авторизация (сохранение в сессию)

<?php

session_start();

$valid_passwords = array ("LOGIN" => "PASSWORD");
$valid_users = array_keys($valid_passwords);

$user = $_SERVER['PHP_AUTH_USER'];
$pass = $_SERVER['PHP_AUTH_PW'];

$validated = isset($_SESSION['logged']) || ((in_array($user, $valid_users)) && ($pass == $valid_passwords[$user]));

if (!$validated) {  
    header('WWW-Authenticate: Basic realm="My Realm"');  
    header('HTTP/1.0 401 Unauthorized');  
    die ("Not authorized");  
} else {  
    $_SESSION['logged'] = date(time());  
}