package remoto;
import java.rmi.Remote;
import java.rmi.RemoteException;
public interface Mensageiro extends Remote {

    void enviarMensagem(String msg) throws RemoteException;

    String lerMensagem() throws RemoteException;

}
/**********************************************************************************************/
package remoto;
import java.rmi.RemoteException;
import java.rmi.server.UnicastRemoteObject;
public class MensageiroImpl extends UnicastRemoteObject implements Mensageiro {

    public MensageiroImpl() throws RemoteException {
        super();
    }

    @Override
    public void enviarMensagem(String msg) throws RemoteException {
        System.out.println(msg);
    }

    @Override
    public String lerMensagem() throws RemoteException {
        return "Ola mundo meu ovo!";
    }

}
/**********************************************************************************************/
import remoto.*;
import java.rmi.registry.Registry;
import java.rmi.registry.LocateRegistry;
import java.rmi.Naming;
import java.rmi.server.*;
public class MensageiroServer {
    public static void main(String[] args) {
        try {
            MensageiroImpl m = new MensageiroImpl();
            LocateRegistry.createRegistry(1099);
            Registry registro = LocateRegistry.getRegistry();
            registro.bind("MensageiroService", m);
            System.out.println("Servidor no ar.");
        } catch (Exception e) {
            System.out.println("Erro no servidor: " + e);
        }
    }
}
/**********************************************************************************************/
I'm using Mint,with NetBeans 7.1.2 and typing java -version in terminal it appears:
java version "1.6.0_26"
Java(TM) SE Runtime Environment (build 1.6.0_26-b03)
Java HotSpot(TM) Client VM (build 20.1-b02, mixed mode, sharing)