RMI object passing problem

hi experts,
 
   in my rmi application, i want to sent server CLASS_A type objects and i designed server interface that way, then at the client side i wrote objects extending CLASS_A so that they would have common methods and be recognized by the rmi server. The problem is there is sometihng wrong and i get the following exception:


java.rmi.ServerException: RemoteException occurred in server thread; nested exception is:
      java.rmi.UnmarshalException: error unmarshalling arguments; nested exception is:
      java.lang.ClassNotFoundException: client.testobject (no security manager: RMI class loader disabled)
      at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:325)
      at sun.rmi.transport.Transport$1.run(Transport.java:153)
      at java.security.AccessController.doPrivileged(Native Method)
      at sun.rmi.transport.Transport.serviceCall(Transport.java:149)
      at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:460)
      at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:701)
      at java.lang.Thread.run(Thread.java:595)
      at sun.rmi.transport.StreamRemoteCall.exceptionReceivedFromServer(StreamRemoteCall.java:247)
      at sun.rmi.transport.StreamRemoteCall.executeCall(StreamRemoteCall.java:223)
      at sun.rmi.server.UnicastRef.invoke(UnicastRef.java:126)
      at java.rmi.server.RemoteObjectInvocationHandler.invokeRemoteMethod(RemoteObjectInvocationHandler.java:179)
      at java.rmi.server.RemoteObjectInvocationHandler.invoke(RemoteObjectInvocationHandler.java:132)
      at $Proxy0.pass(Unknown Source)
      at client.clientTest.Connect(clientTest.java:35)
      at client.clientTest.<init>(clientTest.java:26)
      at client.Main.main(Main.java:23)
Caused by: java.rmi.UnmarshalException: error unmarshalling arguments; nested exception is:
      java.lang.ClassNotFoundException: client.testProc (no security manager: RMI class loader disabled)
      at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:285)
      at sun.rmi.transport.Transport$1.run(Transport.java:153)
      at java.security.AccessController.doPrivileged(Native Method)
      at sun.rmi.transport.Transport.serviceCall(Transport.java:149)
      at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:460)
      at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:701)
      at java.lang.Thread.run(Thread.java:595)
Caused by: java.lang.ClassNotFoundException: client.testProc (no security manager: RMI class loader disabled)
      at sun.rmi.server.LoaderHandler.loadClass(LoaderHandler.java:371)
      at sun.rmi.server.LoaderHandler.loadClass(LoaderHandler.java:165)
      at java.rmi.server.RMIClassLoader$2.loadClass(RMIClassLoader.java:620)
      at java.rmi.server.RMIClassLoader.loadClass(RMIClassLoader.java:247)
      at sun.rmi.server.MarshalInputStream.resolveClass(MarshalInputStream.java:197)
      at java.io.ObjectInputStream.readNonProxyDesc(ObjectInputStream.java:1538)
      at java.io.ObjectInputStream.readClassDesc(ObjectInputStream.java:1460)
      at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1693)
      at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1299)
      at java.io.ObjectInputStream.readObject(ObjectInputStream.java:339)
      at sun.rmi.server.UnicastRef.unmarshalValue(UnicastRef.java:290)
      at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:279)
      ... 6 more


I don't know what is wrong i spent hour but i couldn't figure out the problem.

Does any body can post some usefull code doing the job i said above, i need a base class for sending between nodes and ii want to have other classes extending base class and be able to passed to an rmi server.

thanks