Custom JON plug-in based on jboss-as-7-jmx fails to discover resources due to ClassNotFoundException or NoClassDefFoundError

Issue

• Plugin to detect MBeans in webapp
• I do not see the services exposed

• Agent log reports:

  java.lang.ClassNotFoundException: org.rhq.plugins.jmx.MBeanResourceDiscoveryComponent
  

• Managed Beans (MBeans) are not discovered:

  ERROR [Remoting "endpoint" read-1] (org.xnio.listener)- A channel event listener threw an exception
  java.lang.NoClassDefFoundError: Could not initialize class org.jboss.sasl.digest.DigestMD5Client
      at org.jboss.sasl.digest.DigestMD5ClientFactory.createSaslClient(DigestMD5ClientFactory.java:41)
      at org.jboss.remoting3.remote.ClientConnectionOpenListener$Capabilities$1.run(ClientConnectionOpenListener.java:404)
      at org.jboss.remoting3.remote.ClientConnectionOpenListener$Capabilities$1.run(ClientConnectionOpenListener.java:402)
      at java.security.AccessController.doPrivileged(Native Method)
      at org.jboss.remoting3.remote.ClientConnectionOpenListener$Capabilities.handleEvent(ClientConnectionOpenListener.java:402)
      at org.jboss.remoting3.remote.ClientConnectionOpenListener$Capabilities.handleEvent(ClientConnectionOpenListener.java:229)
      at org.xnio.ChannelListeners.invokeChannelListener(ChannelListeners.java:72)
      at org.xnio.channels.TranslatingSuspendableChannel.handleReadable(TranslatingSuspendableChannel.java:189)
      at org.xnio.channels.TranslatingSuspendableChannel$1.handleEvent(TranslatingSuspendableChannel.java:103)
      at org.xnio.ChannelListeners.invokeChannelListener(ChannelListeners.java:72)
      at org.xnio.channels.TranslatingSuspendableChannel.handleReadable(TranslatingSuspendableChannel.java:189)
      at org.xnio.ssl.JsseConnectedSslStreamChannel.handleReadable(JsseConnectedSslStreamChannel.java:180)
      at org.xnio.channels.TranslatingSuspendableChannel$1.handleEvent(TranslatingSuspendableChannel.java:103)
      at org.xnio.ChannelListeners.invokeChannelListener(ChannelListeners.java:72)
      at org.xnio.nio.NioHandle.run(NioHandle.java:90)
      at org.xnio.nio.WorkerThread.run(WorkerThread.java:198)