Еррор

Привет.

Ребят, PHP выдает вот такой еррор: Notice: Undefined index: PHP_AUTH_USER in /var/www/html/hunters/include/functions.php on line 58, вот код:

function httpauth(){

global $config;



if ($_SERVER['PHP_AUTH_USER'] != $config['login'] || md5($_SERVER['PHP_AUTH_PW'])!= $config['password']) 

{

    header('WWW-Authenticate: Basic realm= "Admin Panel"');

    header('HTTP/1.0 401 Unauthorized');

    die("You have entered an incorrect username or password.");

}

 }