XML : WebService returns 409 it seems to be dropping the encoding=utf-8 how could this happen

This VBScript posts an XML document to a webService:

      Dim xmlhttp, oXML, sourceURL, WSURL, WSUserName, WSPassword, XMLResponse      sourceURL = "C:\temp\myFileName.xml"      WSURL = "https://mywebServiceURL"      WSUserName = "myUserName"      WSPassword = "myPassword"        Set xmlhttp = CreateObject("Microsoft.XMLHTTP")         Set oXML = CreateObject("Microsoft.XMLDOM")          oXML.load(sourceURL)         xmlhttp.open "POST", WSURL, false, WSUserName, WSPassword         xmlhttp.setRequestHeader "Content-type", "application/x-www-form-urlencoded; charset=UTF-8"         xmlhttp.setRequestHeader "Content-length", Len(oXML.xml)         xmlhttp.setRequestHeader "Connection", "close"         xmlhttp.setRequestHeader "soapAction", "processRequest"         xmlhttp.send(oXML.xml)          writeLog "XML len = " & Len(oXML.xml)      writeLog "readyState = " & xmlhttp.readyState           If(xmlhttp.readyState = 4) then             WSStatus = xmlhttp.status          writeLog "WSStatus = " & WSStatus          WSResponse = xmlhttp.responseText             writeLog "WSResponse = " & WSResponse          WSResponse = xmlhttp.responseBody           writeLog "WSResponseBody = " & WSResponseBody      else          writeLog "ERROR : readyState = " & xmlhttp.readyState & " : "      end if    

There are no errors, all appears to be fine. The length is correct, the readyState is 4 however the WS returns an HTTP 409. The custom message returned is 'inbound not ok encoding="UTF-8" is missing'

This implies that this node is missing the encoding="utf-8"? however its not. Its 100% there. The XML looks like so:

      <?xml version="1.0" encoding="utf-8"?>      <ORDERS05>        <IDOC BEGIN="1">          <EDI_DC40 SEGMENT="1">            <TABNAM><![CDATA[EDI_DC40]]></TABNAM>            <IDOCTYP>aaa</IDOCTYP>            <MESTYP>sss</MESTYP>            <SNDPOR>ddd</SNDPOR>          </EDI_DC40>        </IDOC>      </ORDERS05>    

Here is the start of the log trace from the webService people. Note the

      POST /dir/anotherDir HTTP/1.1      content-type: application/x-www-form-urlencoded; charset=UTF-8      connection: close      soapaction: processRequest      accept-language: en-au      content-length: 4699      accept: */*      user-agent: Mozilla/4.0 (compatible; Win32; WinHttp.WinHttpRequest.5)      host: test.aURLHere.co.nz      clientprotocol: https      ssl_cipher_usekeysize: 128      ssl_cipher_suite: 0005      <?xml version="1.0"?>      <ORDERS05>       <IDOC BEGIN="1">        <EDI_DC40 SEGMENT="1">         <TABNAM><![CDATA[EDI_DC40]]></TABNAM>         <IDOCTYP>aaa</IDOCTYP>         <MESTYP>bbb</MESTYP>         <SNDPOR>ccc</SNDPOR>    

Is is possible my sending has the issue, or could this be being dropped by the webService??? Very stuck on this one. Is it the senders issue or the receiver?