To allow IIOP remote references to be transmitted over the RMI native protocol
RMI needs to allow an implementation of java.rmi.Remote that is not a
java.rmi.server.RemoteStub to be serialized when marshalled during a
remote call. Currently, a StubNotFoundException will be thrown in the
case that the object implements Remote, but is not a RemoteStub. If the
Remote object is not exported to the RMI native runtime and no stub instance
can be found for that remote object, the object should be allowed to
be serialized so that foreign stub types can be sent in RMI calls.