Description of problem:

Manual discovery scan triggers a ClassCastException.  Does not seem to affect discovery and import of SOA instance.


---
Exception in agent.log

2013-11-18 15:31:14,201 INFO  [InventoryManager.discovery-1] (rhq.core.pc.inventory.InventoryManager)- Syncing local inventory with Server inventory...
2013-11-18 15:31:14,203 INFO  [InventoryManager.discovery-1] (rhq.core.pc.inventory.RuntimeDiscoveryExecutor)- Executing runtime discovery scan rooted at [platform]...
2013-11-18 15:31:14,841 INFO  [InventoryManager.availability-1] (rhq.core.pc.inventory.AvailabilityExecutor)- Scan Ended   : Mon Nov 18 15:31:14 EST 2013 : Scan [startTime=138480667
3719, endTime=1384806674841, runtime=1122, isFull=true, isForced=false, numResources=638, numGetAvailabilityCalls=27, numScheduledRandomly=0, numPushedByInterval=26, numAvailability
Changes=0, numDeferToParent=0]
2013-11-18 15:31:22,825 WARN  [InventoryManager.discovery-1] (rhq.core.pc.inventory.InventoryManager)- Failure during discovery for [Deployments] Resources - failed after 1 ms.
java.lang.Exception: Discovery component invocation failed.
        at org.rhq.core.pc.util.DiscoveryComponentProxyFactory$ComponentInvocationThread.call(DiscoveryComponentProxyFactory.java:309)
        at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
        at java.util.concurrent.FutureTask.run(FutureTask.java:166)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
        at java.lang.Thread.run(Thread.java:679)
Caused by: java.lang.ClassCastException: org.rhq.modules.plugins.jbossas7.ManagedASComponent cannot be cast to org.rhq.modules.plugins.jbossas7.BaseServerComponent
        at org.switchyard.rhq.plugin.SwitchYardDiscoveryComponent.discoverResources(SwitchYardDiscoveryComponent.java:67)
        at sun.reflect.GeneratedMethodAccessor29.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:616)
        at org.rhq.core.pc.util.DiscoveryComponentProxyFactory$ComponentInvocationThread.call(DiscoveryComponentProxyFactory.java:305)
        ... 5 more



Version-Release number of selected component (if applicable):
JON ER5 build

How reproducible:
100%

Steps to Reproduce:
1. Install JON server, switchyard plugin, agent
2. Inventory agent
3. Perform manual discovery (agent platform right click -> Operations -> Manual autodiscovery)