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use SOAP::Lite +trace => 'all';
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SOAP::Transport::HTTP::Client::send_receive: HTTP/1.1 500 Internal Server Error.
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    <soap:Fault>
      <faultcode>soap:VersionMismatch</faultcode>
      <faultstring>System.Web.Services.Protocols.SoapException: Possible SOAP version mismatch: Envelope namespace http://schemas.xmlsoap.org/wsdl/soap/ was unexpected. Expecting http://schemas.xmlsoap.org/soap/envelope/.
   at System.Web.Services.Protocols.SoapServerProtocol.CheckHelperVersion()
   at System.Web.Services.Protocols.SoapServerProtocol.ReadParameters()
   at System.Web.Services.Protocols.WebServiceHandler.Invoke()
   at System.Web.Services.Protocols.WebServiceHandler.CoreProcessRequest()</faultstring>
      <detail />
    </soap:Fault>