POST data to server with GPRS

Hi!

I got this project where I am supposed to send a bunch of data from my Arduino Uno with an Arduino GSM shield to a server, but I can't seem to understand how the POST request should look like. What I have now is:

if (client.connect(server, port))
{
    Serial.println("connected");
    // Make a HTTP request:
    client.println( "POST /Service HTTP/1.1" );
    client.println( "Host: 212.214.80.136:8124" );
    client.println( "Content-Type: text/xml; charset=utf-8" );
    client.println( "SOAPAction: \"publishXmlEvent\"" );
    client.println( "Connection: Close" );
    client.println();
    client.println( DATA TO BE SENT );
    client.println();
}

The data to be sent will look like this:

<?xml version="1.0" encoding="utf-8"?>
<soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <soap:Body>
    <publishXmlEvent xmlns="http://eventmanager.linksmart.eu">
      <eventXmlString>
        &lt;?xml version="1.0" encoding="utf-8"?&gt;
        &lt;Event xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" about="f4605a3b-cad6-4198-a4d2-9760e799aa81" prefix="inertia:http://ns.inertia.eu/ontologies linksmart:http://linksmart.org/Ontologies/1.0#Draft" eventStatus="Production" schemaVersion="0.5.0" systemsID="LinkSmart" xmlns="http://linksmart.org/Event/1.0"&gt;
        &lt;EventMeta&gt;
        &lt;EventType typeof="TempSensorDevice" /&gt;
        &lt;Topic typeof="OBSERVATION" /&gt;
        &lt;/EventMeta&gt;
        &lt;Content&gt;
        &lt;IoTEntity xmlns="http://linksmart.org/IoTEntity/1.0"&gt;
        &lt;Name&gt;TempSensorDevice&lt;/Name&gt;
        &lt;IoTProperty about="01842FD8:TempSensorDevice" typeof="inertia:TempSensorDevice"&gt;
        &lt;IoTStateObservation&gt;
        &lt;Value&gt;33&lt;/Value&gt;
        &lt;/IoTStateObservation&gt;
        &lt;/IoTProperty&gt;
        &lt;/IoTEntity&gt;
        &lt;/Content&gt;
        &lt;/Event&gt;	
      </eventXmlString>
    </publishXmlEvent>
  </soap:Body>
</soap:Envelope>

I'm using a Arduino Uno r3 with an Arduino GSM shield and I am using the web client example as a base for the project. I don't know if the data to be sent is to much for the arduino to handle...