Missing/Invalid SOAP Envelope

I have set-up a mockService to send a HTTP response to my client. My SOAP UI project is able to find the response, but whilst sending the response, the following error crops up.

2013-02-11 21:18:29,363 ERROR [errorlog] com.eviware.soapui.impl.wsdl.mock.DispatchException: org.apache.xmlbeans.XmlException: Missing/Invalid SOAP Envelope, expecting [{http://schemas.xmlsoap.org/soap/envelope/}Envelope]
com.eviware.soapui.impl.wsdl.mock.DispatchException: org.apache.xmlbeans.XmlException: Missing/Invalid SOAP Envelope, expecting [{http://schemas.xmlsoap.org/soap/envelope/}Envelope]
at com.eviware.soapui.impl.wsdl.mock.WsdlMockRunner.dispatchPostRequest(WsdlMockRunner.java:327)
at com.eviware.soapui.impl.wsdl.mock.WsdlMockRunner.dispatchRequest(WsdlMockRunner.java:375)
at com.eviware.soapui.monitor.JettyMockEngine$ServerHandler.handle(JettyMockEngine.java:715)
at org.mortbay.jetty.handler.HandlerCollection.handle(HandlerCollection.java:114)
at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
at org.mortbay.jetty.Server.handle(Server.java:326)
at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)
at org.mortbay.jetty.HttpConnection$RequestHandler.content(HttpConnection.java:945)
at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:756)
at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:218)
at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)
at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:410)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:619)
Caused by: org.apache.xmlbeans.XmlException: Missing/Invalid SOAP Envelope, expecting [{http://schemas.xmlsoap.org/soap/envelope/}Envelope]
at com.eviware.soapui.impl.wsdl.support.soap.SoapUtils.getBodyElement(SoapUtils.java:134)
at com.eviware.soapui.impl.wsdl.support.soap.SoapUtils.getContentElement(SoapUtils.java:171)
at com.eviware.soapui.impl.wsdl.support.soap.SoapUtils.findOperationForRequest(SoapUtils.java:207)
at com.eviware.soapui.impl.wsdl.mock.WsdlMockRunner.dispatchPostRequest(WsdlMockRunner.java:250)
... 14 more


Am I right in inferring that my mock service is expecting a SOAP payload? Please let me know if there is a setting on my onRequestScript that I am missing. I tried trying to implement what was listed on the link "http://www.soapui.org/Service-Mocking/mocking-rest-services.html", but in vain. Has anyone encountered this issue and what is the resolution? The SOAP Version I am using is 4.5.0. Please let me know if you require any other information.

Thanks in advance,
Suren