Hyperic 4.6 custom pdk plugin not working

This should be easy, but I'm having problems writing a custom plugin to create a new service that displays metrics about my application running in tomcat server.  I have tested my MBean against jconole and it's fine.

Plugin looks something like this:

<plugin name="Obsidian">
       <!--<property name="PLUGIN_VERSION" value="1.0"/>-->
       <service name="Obsidian-Midtier">

               <!-- the Obsidian MBean objectname -->
               <property name="OBJECT_NAME" value="com.sas.obsidian:service=Signature,name=QueryStatistics"/>
      
               <!-- autodiscover -->
               <plugin type="autoinventory"/>              
              
               <!-- list measurements to include -->
               <plugin type="measurement" class="org.hyperic.hq.product.jmx.MxMeasurementPlugin"/>
              
              
               <filter name="template" value="${OBJECT_NAME}:${alias}"/>
               <metric name="Event Rate" alias="EventRate" indicator="true"/>
               <metric name="Event Rate Sampling Size" alias="EventRateSampleSize" indicator="true"/>
               <metric name="Event Query Count" alias="EventQueryCount" indicator="true"/>

               <!-- list operations -->
               <plugin type="control" class="org.hyperic.hq.product.jmx.MxControlPlugin"/>
               <actions include="setEventRateSampleSize,getEventQueryCount,getVisitorQueryCount,getVisitorQueryCountByEvent"/>
       </service>
</plugin>

How can I get my service to be auto-discovered?  Do I need to associate it with a server?  Or will it just search all servers?

Any help is greatly appreciated.

I would love to see some errors or something stating that I have something wrong.  How can I test my plugin for errors? When I run hq-pdk.jar -p obsidian -m discover, I just get "0 servers detected".  No errors.

Thanks.