мыльный веб-сервис с Symfony

Я пишу веб-сервис с Symfony2, который находится в этом руководство.

мой маршрут:

_soap:
path:      /soap
defaults:  { _controller: AcmeSoapBundle:Default:index}

мой конфиг:

services:
hello_service:
class: Acme\SoapBundle\Services\HelloService
arguments: ["@mailer"]

мой сервис:

namespace Acme\SoapBundle\Services;

class HelloService
{
private $mailer;

public function __construct(\Swift_Mailer $mailer)
{
$this->mailer = $mailer;
}

public function hello($name)
{

$message = \Swift_Message::newInstance()
->setTo('[email protected]')
->setSubject('Hello Service')
->setBody($name . ' says hi!');

$this->mailer->send($message);

return 'Hello, '.$name;
}
}

мой контроллер:

namespace Acme\SoapBundle\Controller;

use Symfony\Bundle\FrameworkBundle\Controller\Controller;
use Symfony\Component\HttpFoundation\Response;

class DefaultController extends Controller
{
public function indexAction()
{
$server = new \SoapServer('hello.wsdl');
$server->setObject($this->get('hello_service'));

$response = new Response();
$response->headers->set('Content-Type', 'text/xml; charset=ISO-8859-1');

ob_start();
$server->handle();
$response->setContent(ob_get_clean());

return $response;
}
}

hello.wsdl (web / hello.wsdl)

    <?xml version="1.0" encoding="ISO-8859-1"?>
<definitions xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/"xmlns:xsd="http://www.w3.org/2001/XMLSchema"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/"xmlns:tns="urn:arnleadservicewsdl"xmlns:soap="http://schemas.xmlsoap.org/wsdl/soap/"xmlns:wsdl="http://schemas.xmlsoap.org/wsdl/"xmlns="http://schemas.xmlsoap.org/wsdl/"targetNamespace="urn:helloservicewsdl">

<types>
<xsd:schema targetNamespace="urn:hellowsdl">
<xsd:import namespace="http://schemas.xmlsoap.org/soap/encoding/" />
<xsd:import namespace="http://schemas.xmlsoap.org/wsdl/" />
</xsd:schema>
</types>

<message name="helloRequest">
<part name="name" type="xsd:string" />
</message>

<message name="helloResponse">
<part name="return" type="xsd:string" />
</message>

<portType name="hellowsdlPortType">
<operation name="hello">
<documentation>Hello World</documentation>
<input message="tns:helloRequest"/>
<output message="tns:helloResponse"/>
</operation>
</portType>

<binding name="hellowsdlBinding" type="tns:hellowsdlPortType">
<soap:binding style="rpc" transport="http://schemas.xmlsoap.org/soap/http"/>
<operation name="hello">
<soap:operation soapAction="urn:arnleadservicewsdl#hello" style="rpc"/>

<input>
<soap:body use="encoded" namespace="urn:hellowsdl"encodingStyle="http://schemas.xmlsoap.org/soap/encoding/"/>
</input>

<output>
<soap:body use="encoded" namespace="urn:hellowsdl"encodingStyle="http://schemas.xmlsoap.org/soap/encoding/"/>
</output>
</operation>
</binding>

<service name="hellowsdl">
<port name="hellowsdlPort" binding="tns:hellowsdlBinding">
<soap:address location="http://example.com/app.php/soap" />
</port>
</service>
</definitions>

но я вижу ниже ошибку:

XML Parsing Error: no element found
Location: http://xxx.xxxx.xxx/unproject/web/app_dev.php/soap
Line Number 1, Column 1:

Как я могу исправить эту проблему?
Спасибо за вашу помощь