Recreate a php session

recreate_session.php

<?php

define('SESSION_TIMEOUT', '1800'); // 30 minutes

session_name('fuckIE');
session_start();

// ...bla bla

if (isset($_SESSION['last_activity']) && (time() - $_SESSION['last_activity'] > SESSION_TIMEOUT)) {
	// last request was more than timeout seconds ago
	session_regenerate_id(true);
	session_destroy();
	unset($_SESSION);
	session_start();
}
$_SESSION['last_activity'] = time();

// ...bla bla

?>