title: RelayUtils Error while building Passthrough stream-error in wso2esb
body: <p>I'm using wso2esb 4.7.0 and wso2dss 3.0.0..I have written a query in wso2dss.It's working fine in dss. also but when i wish to work with wso2esb <strong>in sequence mediator it shows error</strong> as above</p>
  
  <pre><code> ERROR - RelayUtils Error while building Passthrough stream
  org.apache.axiom.om.OMException: com.ctc.wstx.exc.WstxEOFException: Unexpected EOF in prolog
   at [row,col {unknown-source}]: [1,0]
      at org.apache.axiom.om.impl.builder.StAXOMBuilder.next(StAXOMBuilder.java:296)
      at org.apache.axiom.soap.impl.builder.StAXSOAPModelBuilder.getSOAPEnvelope(StAXSOAPModelBuilder.java:204)
      at org.apache.axiom.soap.impl.builder.StAXSOAPModelBuilder.&lt;init&gt;(StAXSOAPModelBuilder.java:154)
      at org.apache.axiom.om.impl.AbstractOMMetaFactory.createStAXSOAPModelBuilder(AbstractOMMetaFactory.java:73)
      at org.apache.axiom.om.impl.AbstractOMMetaFactory.createSOAPModelBuilder(AbstractOMMetaFactory.java:79)
      at org.apache.axiom.om.OMXMLBuilderFactory.createSOAPModelBuilder(OMXMLBuilderFactory.java:196)
      at org.apache.axis2.builder.SOAPBuilder.processDocument(SOAPBuilder.java:55)
      at org.apache.synapse.transport.passthru.util.DeferredMessageBuilder.getDocument(DeferredMessageBuilder.java:118)
      at org.apache.synapse.transport.passthru.util.RelayUtils.builldMessage(RelayUtils.java:116)
      at org.apache.synapse.transport.passthru.util.RelayUtils.buildMessage(RelayUtils.java:91)
      at org.apache.synapse.mediators.AbstractListMediator.mediate(AbstractListMediator.java:62)
      at org.apache.synapse.mediators.base.SequenceMediator.mediate(SequenceMediator.java:114)
      at org.apache.synapse.core.axis2.Axis2SynapseEnvironment.injectMessage(Axis2SynapseEnvironment.java:232)
      at org.apache.synapse.core.axis2.SynapseCallbackReceiver.handleMessage(SynapseCallbackReceiver.java:443)
      at org.apache.synapse.core.axis2.SynapseCallbackReceiver.receive(SynapseCallbackReceiver.java:166)
      at org.apache.axis2.engine.AxisEngine.receive(AxisEngine.java:180)
      at org.apache.synapse.transport.passthru.ClientWorker.run(ClientWorker.java:222)
      at org.apache.axis2.transport.base.threads.NativeWorkerPool$1.run(NativeWorkerPool.java:172)
      at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1146)
      at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
      at java.lang.Thread.run(Thread.java:679)
  Caused by: com.ctc.wstx.exc.WstxEOFException: Unexpected EOF in prolog
   at [row,col {unknown-source}]: [1,0]
      at com.ctc.wstx.sr.StreamScanner.throwUnexpectedEOF(StreamScanner.java:677)
      at com.ctc.wstx.sr.BasicStreamReader.handleEOF(BasicStreamReader.java:2116)
      at com.ctc.wstx.sr.BasicStreamReader.nextFromProlog(BasicStreamReader.java:2022)
      at com.ctc.wstx.sr.BasicStreamReader.next(BasicStreamReader.java:1114)
      at org.apache.axiom.util.stax.wrapper.XMLStreamReaderWrapper.next(XMLStreamReaderWrapper.java:225)
      at org.apache.axiom.util.stax.dialect.DisallowDoctypeDeclStreamReaderWrapper.next(DisallowDoctypeDeclStreamReaderWrapper.java:34)
      at org.apache.axiom.util.stax.wrapper.XMLStreamReaderWrapper.next(XMLStreamReaderWrapper.java:225)
      at org.apache.axiom.om.impl.builder.StAXOMBuilder.parserNext(StAXOMBuilder.java:681)
      at org.apache.axiom.om.impl.builder.StAXOMBuilder.next(StAXOMBuilder.java:214)
      ... 20 more
  
          .
          .
  </code></pre>
  
  <p>My proxy service is :</p>
  
  <pre><code>&lt;inSequence&gt;
           &lt;property name="messageType" value="application/json" scope="axis2"/&gt;
           &lt;property name="username"
                     expression="//username/text()"
                     scope="default"
                     type="STRING"/&gt;
           &lt;property name="userid"
                     expression="//userid/text()"
                     scope="default"
                     type="STRING"/&gt;
           &lt;log&gt;
              &lt;property name="username" expression="get-property('username')"/&gt;
              &lt;property name="userid" expression="get-property('userid')"/&gt;
           &lt;/log&gt;
           &lt;payloadFactory media-type="xml"&gt;
              &lt;format&gt;
                 &lt;p:trail_op xmlns:p="http://ws.wso2.org/dataservice"&gt;
                    &lt;p:username&gt;$1&lt;/p:username&gt;
                    &lt;p:userid&gt;$2&lt;/p:userid&gt;
                 &lt;/p:trail_op&gt;
              &lt;/format&gt;
              &lt;args&gt;
                 &lt;arg evaluator="xml" expression="get-property('username')"/&gt;
                 &lt;arg evaluator="xml" expression="get-property('userid')"/&gt;
              &lt;/args&gt;
           &lt;/payloadFactory&gt;
           &lt;header name="Action" value=""/&gt;
           &lt;property name="SOAPAction" value="" scope="transport"/&gt;
           &lt;send receive="Capp_Login_seq1"&gt;
              &lt;endpoint&gt;
                 &lt;address uri="http://192.168.1.23:9764/services/Capp_muser_dataservice/"
                          format="soap12"/&gt;
              &lt;/endpoint&gt;
           &lt;/send&gt;
           &lt;log level="full"/&gt;
        &lt;/inSequence&gt;
        &lt;outSequence&gt;
           &lt;send/&gt;
        &lt;/outSequence&gt;
  </code></pre>
  
  <p>and sequence is: </p>
  
  <pre><code> &lt;sequence xmlns="http://ws.apache.org/ns/synapse" name="Capp_Login_seq1"&gt;
     &lt;property name="messageType" value="application/json" scope="axis2"/&gt;
     &lt;property xmlns:ns="http://org.apache.synapse/xsd" xmlns:s="http://ws.wso2.org/dataservice" name="userid" expression="get-property('userid')" scope="default" type="STRING"/&gt;
     &lt;log&gt;
        &lt;property xmlns:ns="http://org.apache.synapse/xsd" name="userid" expression="get-property('userid')"/&gt;
     &lt;/log&gt;
     &lt;send/&gt;
  &lt;/sequence&gt;
  </code></pre>
  
  <p>I'm sending request like:</p>
  
  <pre><code>curl -v -H "Accept:application/json" -H "Content-Type:application/json"  -d '{"username":"Harry","userid":"347367127872701992"}' http://youtility-desktop:8282/services/Capp_LoginProxy
  </code></pre>
  
  <p>How should i fix the error? Please let me know..</p>