Add SOAP Envelope to request?

Hi,

I'm trying to invoke a SOAP request for a customer and the error response from the web service is:

<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/">

   <soapenv:Body>

      <soapenv:Fault>

         <faultcode>Server</faultcode>

         <faultstring>org.apache.xmlbeans.XmlException: Missing/Invalid SOAP Envelope, expecting [{http://schemas.xmlsoap.org/soap/envelope/}Envelope]</faultstring>

      </soapenv:Fault>

   </soapenv:Body>

</soapenv:Envelope>

Using the SOAPInterceptor I can view the request that was sent to the server. If I take that output, manually add the code below and then send it to the web service using SoapUI the correct response is recieved:

<soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">

   <soap:Body>

...vCO generated request XML...

   </soap:Body>

</soap:Envelope>

How do I add the SOAP envelope to the request? The code being used in the Orchestrator workflow is the standard code generated by the "Generate a new workflow from a SOAP operation", with the SOAPInterceptor added.

Thanks,

Sam