Call a WCF Service from Linux Nusoap

include('lib/nusoap.php');

$client = new nusoap_client('http://url.svc?wsdl', 'wsdl',
                $proxyhost, $proxyport, $proxyusername, $proxypassword);
$err = $client->getError();
if ($err) {
echo "Constructor error";
exit;
}
$client->soap_defencoding = 'UTF-8';
$result = $client->call('DoWork');
echo $result['DoWorkResult'];
//echo $client->debug_str;
echo "\n";