Unable to get Martin Gudgin's XML-->MTOM online converter tool to work

Hi Folks,
 
I am trying to use the XML-->MTOM online tool that Martin Gudgin created [1]
but am not having any success. 
 
I have written a Java program which reads in Martin's test1a.xml file,
embeds it in an HTTP POST message and sends it to his tool.  Below is the
HTTP message that I POST to the tool (base64 data omitted).  Any ideas on
what I am doing wrong?
 
POST /dotnet/mtom/mtomecho.ashx HTTP/1.0
Content-type: application/soap+xml
Content-length: 28469
 
<s:Envelope xmlns:s="http://www.w3.org/2003/05/soap-envelope"
<http://www.w3.org/2003/05/soap-envelope> >
    <s:Body>
        <x:Data xmlns:x=" <http://example.org/mtom/data>
http://example.org/mtom/data">
            --- test 1a.xml base64 data ---
       </x:Data>
    </s:Body>
</s:Envelope>
 
Here is the error message I get when I run my Java program:
 
java.io.IOException: Server returned HTTP response code: 400 for URL: 
http://martingudgin-2.dsl.easynet.co.uk/dotnet/mtom/mtomecho.ashx
 
HTTP 400 indicates a client error.  Apparently, something is incorrect with
my HTTP message, but I do not know what that might be.  Any thoughts would
be much appreciated.  Thanks!
 
/Roger
 
[1] http://martingudgin-2.dsl.easynet.co.uk/dotnet/mtom/mtomecho.ashx