When I tried to communicate with RMI server asynchronously, I got the following error message: java.rmi.ServerException: RemoteException occurred in server thread; nested exce ption is: java.rmi.UnmarshalException: invalid method hash at sun.rmi.transport.StreamRemoteCall.exceptionReceivedFromServer(StreamRemoteCall.java:248) at sun.rmi.transport.StreamRemoteCall.executeCall(StreamRemoteCall.java:223) at sun.rmi.server.UnicastRef.invoke(UnicastRef.java:136) at CrossOverMutationImpl_Stub.performCrossOverMutation(Unknown Source) at GeneticFnApproximation.computeCoefficients(GeneticFnApproximation.java:573) Any help is appreciated.    More>>