title: wso2mb 100% cpu usage after message submit
body: <p>I want to try out an WSO2MB (Message Broker) (version 2.2.0) implementation, but as soon as I put a message on the queue (via an WSO2ESB message store) the CPU of message broker goes to 100% and only comes down again after purging the queue and restarting MB. 
  Is this a know issue to anyone? </p>
  
  <p>If I cannot solve this, I would need to change MB for Apache ActiveMQ, but that would be such a waste of time when I would like to have all products of one supplier: WSO2... </p>