Removing the namespace from SOAP request

I have imported a WSDL and use it to send a SOAP request. It looks like this:

<?xml version="1.0"?>
<SOAP-ENV:Envelope 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">
    <SOAP-ENV:Body>
        <Calculate xmlns="urn:xx.WSDL.xxxxxWebService">
            <ContractdocumentIn>
                <AL>
                ...More XML...

The problem is the xmlns="urn:xx.WSDL.xxxxxWebService" part in the Calculate element. The web service cannot accept this. The web service doesn't like namespaces like this...
Using SoapUI I found this request to work just fine:

<SOAP-ENV:Envelope xmlns:SOAP-ENV="http://www.w3.org/2003/05/soap-envelope" xmlns:col="http://example.com.service.xxx/">
    <SOAP-ENV:Body>
        <col:Calculate>
            <ContractdocumentIn>
                <AL>
                    ...More XML...

So, how do I change the request from the first to the second version? (Without using dirty tricks!)
(Re-importing is not a problem if this would result in the proper request format.)

Again: no dirty tricks allowed, like hacking the request stream to modify it!

And while I haven't completely tested it, it seems that C#/VS2010 and Delphi 2010 are also unable to use the web service that I'm trying to call. A web service that seems to be written in Java. SoapUI happens to be written in Java, thus we have a Java client talking to a Java service, which seems to work just fine. But any other client?
Anyways, time to add two more tags: "Java", since it's a Java service, and "vs2010" because .NET also dislikes this service.
And I was about