Swift-Mailer 4.0.0 Fatal error:...?

Hallo,hab mir den neuen swift-mailer geholt,und hab jetzt das problem,dass folgender error angezeigt wird:

Fatal error: Call to undefined function spl_autoload_register() in /usr/export/www/vhosts/funnetwork/hosting/dulling/lib/swift_required.php on line 47

Die datei swift_required.php sieht so aus:

<code>
<?php

/*
Autoloader and dependency injector for Swift Mailer.

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.

*/

define('SWIFT_CLASS_DIRECTORY', dirname(__FILE__) . '/classes');
define('SWIFT_MAP_DIRECTORY', dirname(__FILE__) . '/dependency_maps');
define('SWIFT_CLASSPATH', SWIFT_CLASS_DIRECTORY);

/**
* Swift's autoload implementation.
* @param string $class
*/
function swift_autoload($class)
{
if (substr($class, 0, 5) != 'Swift')
{
return;
}

foreach (explode(PATH_SEPARATOR, SWIFT_CLASSPATH) as $classPath)
{
$path = $classPath . '/' . str_replace('_', '/', $class) . '.php';

if (file_exists($path))
{
require_once $path;
}
}
}

spl_autoload_register('swift_autoload');

//Load in dependency maps
require_once SWIFT_MAP_DIRECTORY . '/cache_deps.php';
require_once SWIFT_MAP_DIRECTORY . '/mime_deps.php';
require_once SWIFT_MAP_DIRECTORY . '/transport_deps.php';

//Load in global library preferences
require_once dirname(__FILE__) . '/preferences.php';
</code>

die line 47 ist diese:

<code>spl_autoload_register('swift_autoload');</code>

was muss ich tun,damit es funktioniert??

(PS: Mein webspace ist bei funpic.de)