When using jconsole I can see many throws of OperationFailedRuntimeException with message "Duplicate path element". 

Many of MBean operations is not possible because of this issue.

EAP call stack (6.4.0.DR13):

Daemon System Thread [RMI TCP Connection(1)-127.0.0.1] (Suspended (exception OperationFailedRuntimeException))	
	owns: RMIJRMPServerImpl  (id=223)	
	owns: RMIConnectionImpl  (id=224)	
	PathAddress.pathAddress(List<PathElement>) line: 125	
	PathAddress.append(List<PathElement>) line: 219	
	PathAddress.append(PathAddress) line: 239	
	ConcreteResourceRegistration(AbstractResourceRegistration).getSubRegistration(PathAddress) line: 420	
	ConcreteResourceRegistration(AbstractResourceRegistration).getSubModel(PathAddress) line: 412	
	ConcreteResourceRegistration(AbstractResourceRegistration).getSubModel(PathAddress) line: 56	
	ObjectNameAddressUtil.searchPathAddress(PathAddress, ImmutableManagementResourceRegistration, Map<String,String>) line: 152	
	ObjectNameAddressUtil.searchPathAddress(PathAddress, ImmutableManagementResourceRegistration, Map<String,String>) line: 156	
	ObjectNameAddressUtil.searchPathAddress(PathAddress, ImmutableManagementResourceRegistration, Map<String,String>) line: 156	
	ObjectNameAddressUtil.toPathAddress(String, ImmutableManagementResourceRegistration, ObjectName) line: 141	
	ModelControllerMBeanHelper.toPathAddress(ObjectName) line: 192	
	ModelControllerMBeanServerPlugin.addNotificationListener(ObjectName, NotificationListener, NotificationFilter, Object) line: 230	
	PluggableMBeanServerImpl.addNotificationListener(ObjectName, NotificationListener, NotificationFilter, Object) line: 159	
	ArrayNotificationBuffer$1.run() line: 668	
	ArrayNotificationBuffer$1.run() line: 666	
	AccessController.doPrivileged(PrivilegedExceptionAction<T>) line: not available [native method]	
	ArrayNotificationBuffer.addNotificationListener(ObjectName, NotificationListener, NotificationFilter, Object) line: 666	
	ArrayNotificationBuffer.addBufferListener(ObjectName) line: 640	
	ArrayNotificationBuffer.createListeners() line: 631	
	ArrayNotificationBuffer.getNotificationBuffer(MBeanServer, Map<String,?>) line: 153	
	RMIJRMPServerImpl(RMIServerImpl).getNotifBuffer() line: 525	
	RMIConnectionImpl.getServerNotifFwd() line: 201	
	RMIConnectionImpl.doOperation(int, Object[]) line: 1523	
	RMIConnectionImpl.access$300(RMIConnectionImpl, int, Object[]) line: 97	
	RMIConnectionImpl$PrivilegedOperation.run() line: 1328	
	RMIConnectionImpl.doPrivilegedOperation(int, Object[], Subject) line: 1420	
	RMIConnectionImpl.addNotificationListeners(ObjectName[], MarshalledObject[], Subject[]) line: 1023	
	NativeMethodAccessorImpl.invoke0(Method, Object, Object[]) line: not available [native method]	
	NativeMethodAccessorImpl.invoke(Object, Object[]) line: 57	
	DelegatingMethodAccessorImpl.invoke(Object, Object[]) line: 43	
	Method.invoke(Object, Object...) line: 606	
	UnicastServerRef2(UnicastServerRef).dispatch(Remote, RemoteCall) line: 322	
	Transport$1.run() line: 177	
	Transport$1.run() line: 174	
	AccessController.doPrivileged(PrivilegedExceptionAction<T>, AccessControlContext) line: not available [native method]	
	TCPTransport(Transport).serviceCall(RemoteCall) line: 173	
	TCPTransport.handleMessages(Connection, boolean) line: 556	
	TCPTransport$ConnectionHandler.run0() line: 811	
	TCPTransport$ConnectionHandler.run() line: 670	
	ThreadPoolExecutor.runWorker(ThreadPoolExecutor$Worker) line: 1145	
	ThreadPoolExecutor$Worker.run() line: 615	
	Thread.run() line: 745	

Steps to Reproduce:
Use steps from bug 1113908 comment 0.
The exception class is not on client classpath, so you will only see message "ClassNotFoundException: org.jboss.as.controller.OperationFailedRuntimeException (no security manager: RMI class loader disabled)"

A better way to see what's happening is to start the EAP with debug enabled and add Exception breakpoint for org.jboss.as.controller.OperationFailedRuntimeException. Then attach to the EAP with jconsole.