求教EJB ClassCastException问题

请问这种情况是怎么回事，在本地没问题，在两台机器上用EJB就有问题

Trace from server: 1771041267 at host 133.9.2.21 >>
java.lang.ClassCastException: com.test.services.routingservice.routerule.Rule
at com.ibm.rmi.iiop.CDROutputStream.fast_write_abstract_interface(CDROutputStream.java:1201)
at com.ibm.rmi.io.IIOPOutputStream.writeObjectDelegate(IIOPOutputStream.java:155)
at com.ibm.rmi.io.IIOPOutputStream.writeObjectOverride(IIOPOutputStream.java:178)
at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:286)
at java.util.ArrayList.writeObject(ArrayList.java:533)
at java.lang.reflect.Method.invoke(Native Method)
at com.ibm.rmi.io.IIOPOutputStream.invokeObjectWriter(IIOPOutputStream.java:836)
at com.ibm.rmi.io.IIOPOutputStream.outputObject(IIOPOutputStream.java:872)
at com.ibm.rmi.io.IIOPOutputStream.writeSerializable(IIOPOutputStream.java:920)
at com.ibm.rmi.io.IIOPOutputStream.simpleWriteObjectInternal(IIOPOutputStream.java:382)
at com.ibm.rmi.io.IIOPOutputStream.simpleWriteObjectLoop(IIOPOutputStream.java:410)
at com.ibm.rmi.io.IIOPOutputStream.writeObjectDelegate(IIOPOutputStream.java:167)
at com.ibm.rmi.io.IIOPOutputStream.writeObjectOverride(IIOPOutputStream.java:178)
at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:286)
at java.util.Hashtable.writeObject(Hashtable.java:776)
at java.lang.reflect.Method.invoke(Native Method)
at com.ibm.rmi.io.IIOPOutputStream.invokeObjectWriter(IIOPOutputStream.java:836)
at com.ibm.rmi.io.IIOPOutputStream.outputObject(IIOPOutputStream.java:872)
at com.ibm.rmi.io.IIOPOutputStream.writeSerializable(IIOPOutputStream.java:920)
at com.ibm.rmi.io.IIOPOutputStream.simpleWriteObjectInternal(IIOPOutputStream.java:382)
at com.ibm.rmi.io.IIOPOutputStream.simpleWriteObjectLoop(IIOPOutputStream.java:410)
at com.ibm.rmi.io.IIOPOutputStream.simpleWriteObject(IIOPOutputStream.java:467)
at com.ibm.rmi.io.ValueHandlerImpl.writeValue(ValueHandlerImpl.java:154)
at com.ibm.rmi.iiop.CDROutputStream.write_value(CDROutputStream.java:1223)
at com.ibm.rmi.iiop.CDROutputStream.write_value(CDROutputStream.java:1245)
at com.ibm.rmi.iiop.CDROutputStream.write_value(CDROutputStream.java:1205)
at com.test.services.adapters._EJSRemoteStatelessEJBAdapter_5a1670cf_Tie.processServiceRequest(_EJSRemoteStatelessEJBAdapter_5a1670cf_Tie.java:174)
at com.test.services.adapters._EJSRemoteStatelessEJBAdapter_5a1670cf_Tie._invoke(_EJSRemoteStatelessEJBAdapter_5a1670cf_Tie.java:103)
at com.ibm.CORBA.iiop.ServerDelegate.dispatchInvokeHandler(ServerDelegate.java:615)
at com.ibm.CORBA.iiop.ServerDelegate.dispatch(ServerDelegate.java:468)
at com.ibm.rmi.iiop.ORB.process(ORB.java:396)
at com.ibm.CORBA.iiop.ORB.process(ORB.java:1608)
at com.ibm.rmi.iiop.Connection.doWork(Connection.java:2164)
at com.ibm.rmi.iiop.WorkUnitImpl.doWork(WorkUnitImpl.java:63)
at com.ibm.ejs.oa.pool.PooledThread.run(ThreadPool.java:95)
at com.ibm.ws.util.ThreadPool$Worker.run(ThreadPool.java:593)
<< END server: 1771041267 at host 133.9.2.21