Securing Magmi UI access

head.php

 function authenticate($username=”“,$password=”“){ 
require "../../app/Mage.php"; 
Mage::app('default'); 
$user = Mage::getModel('admin/user'); 
$user->login($username,$password); 
$result = $user->getId(); 
return $result ? true : false; 
} 

if (!isset($_SERVER[‘PHP_AUTH_USER’])) { 
header('WWW-Authenticate:Basic realm="Magmi"'); 
header('HTTP/1.0 401 Unauthorized'); 
echo 'You must be logged in to use Magmi'; 
die(); 
} else { 
if (!authenticate($_SERVER['PHP_AUTH_USER'],$_SERVER['PHP_AUTH_PW'])){
header('WWW-Authenticate: Basic realm="Magmi"'); 
header('HTTP/1.0 401 Unauthorized'); 
echo 'You must be logged in to use Magmi'; 
die(); 
} 

} 
/***************** *********************/

Doesn't work in Magento Community 1.9. I put the Magento admin username and password and continues to call me again and again. Should I replace something to make it work?

http://www.buenamarca.com/magmi/web/magmi.php

Thank you!