Newbie Question about Published Web Services

I'm experimenting with a simple orchestration that I've published as web service.  All the Orchestration does is receive a message and  sends it to a file.

I've created a 2nd orchestration that reads a file from a location on the server, transforms it to the multi-part message type compatible with the web service.  When I drop an xml file in the "IN" directory, the 2nd orchestration triggers, succesfully sends the message to the web service.  The web service successfully triggers and sends a message to the "OUT" directory.  However the out directory file does not contain the data, only the schema.

The message sent to the web service is:

<ns0:SchFullCustomer xmlns:ns0="http://TestWebOrchastration.SchFullCustomer">
<FirstName>John</FirstName>
<Surname>Smith</Surname>
<Age>36</Age>
<ID>3412</ID>
</ns0:SchFullCustomer>

And the message received from the web service is:

<?xml version="1.0" encoding="utf-8"?><SchFullCustomer xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="http://TestWebOrchastration.SchFullCustomer">
  <FirstName xmlns="" />
  <Surname xmlns="" />
  <Age xmlns="" />
  <ID xmlns="" />
</SchFullCustomer>

Can someone give me a pointer to where I might be going wrong??  No doubt it's something simple but it's driving me mad!!

Thanks

Sarah