Consumer Proxy Error while executing

Hi Experts,

I had successfully created one proxy for external WSDL file and calling one of proxy method with all proper parameters, then I am getting system exception saying 'SoapFaultCode:5  Server was unable to process request. ---> Value cannot be null.#Parameter name: parms'?

when this error occurs any idea?

I also created  one SOAP UI project with same WSDL file for testing and found that after input the all necessary parameters like SAP then got results saying

         <faultcode>soap:Server</faultcode>

         <faultstring>Server was unable to process request. ---> Value cannot be null.Parameter name: parms</faultstring>

this is exactly mathing with ABAP proxy after executed method.

Now at SOAP UI I had removed the one of tag 'SubmitExSoapIn' (hierarchy is below) then it got successfuly executed at SOAP end, then how we can process this at SAP? is this problem with service provider? any thing we need to handle extra at SAP?

   <soapenv:Header/>

   <soapenv:Body>

      <wsdl:SubmitExSoapIn>

         <wsdl:service>?</wsdl:service>

         <wsdl:parms>

detailed tags:

<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:wsdl="xyz">
   <soapenv:Header/>
   <soapenv:Body>
      <wsdl:SubmitExSoapIn>

         <wsdl:service>abc</wsdl:service>
         <wsdl:parms>
            <wsdl:string>input</wsdl:string>
         </wsdl:parms>

         <wsdl:inDocuments>
            <wsdl:Doc>
               <wsdl:id>html</wsdl:id>
               <wsdl:content></wsdl:content>
            </wsdl:Doc>
         </wsdl:inDocuments>

      </wsdl:SubmitExSoapIn>

   </soapenv:Body>
</soapenv:Envelope>

Thanks,

VijInd