[rules-users] how to invoke rest service on drools server with serialized objects

I installed drools-server (5.2 final) in tomcat and was able to invoke the sample Soap service using SoapUI using Salaboy's excellent blog post instructions. I have modified knowledge-services.xml to add my rule base using a knowledge agent, and changed camel-server.xml to marshal/unmarshal using serialization. The drools-server starts up without error, but when I try to call the rest service from my java client, I get HTTP response: status code = 415, status message = [Unsupported Media Type]. Any suggestions or example of how to do this? I am attaching my xml files. the application-Context-rulesTestIntegrationExamples.xml is the spring bean definition for my client java program.