Here is my action bean where Projectstatus is a simple entity mapped to database table and  EbeExecutor a class which loads some external application logic.

@Name("projectRisk")
@Stateful
@Scope(ScopeType.APPLICATION)
public class ProjectRiskBean extends EbeExecutor(Projectstatus, Projectstatus) implements IProjectRisk {

    private static final String START_NODE = "Input";
    private static final String MODEL_NAME = "ProjectRisk";

    public ProjectRiskBean() {
        super( MODEL_NAME, START_NODE );
    }

    public void injectCurrentProjectRisk( Projectstatus projectstatus ) {
        // set default risk points to make the concept accessible to the EBE 
        projectstatus.setCurrentrisk( "0" );

        // inject project risk into existing project status ==> inputs = outputs
        List<Projectstatus> inputs = Arrays.asList( new Projectstatus[] { projectstatus } );
        List<Projectstatus> outputs = Arrays.asList( new Projectstatus[] { projectstatus } );

        // execute query
        super.execute( inputs, outputs );
    }

    /* (non-Javadoc)
     * @see com.erudine.dashboard.ebe.IProjectRisk#destroy()
     */
    @Remove
    public void destroy() {
        super.dispose();
    }

I have a conversation time out set for 4 mintues.

The Jboss console throws following exception


  16:02:08,159 ERROR [ProjectRiskBean] problem passivation thread
javax.ejb.EJBException: Could not passivate; failed to save state
        at org.jboss.ejb3.cache.simple.StatefulSessionFilePersistenceManager.passivateSession(StatefulSessionFilePersistenceManager.java:406)
        at org.jboss.ejb3.cache.simple.SimpleStatefulCache.passivate(SimpleStatefulCache.java:301)
        at org.jboss.ejb3.cache.simple.SimpleStatefulCache$SessionTimeoutTask.run(SimpleStatefulCache.java:209)
Caused by: java.lang.NullPointerException
        at org.jboss.serial.objectmetamodel.ObjectDescriptorFactory.describeObject(ObjectDescriptorFactory.java:147)
        at org.jboss.serial.objectmetamodel.DataContainer$DataContainerDirectOutput.writeObject(DataContainer.java:206)
        at org.jboss.serial.persister.RegularObjectPersister.writeSlotWithFields(RegularObjectPersister.java:182)
        at org.jboss.serial.persister.RegularObjectPersister.defaultWrite(RegularObjectPersister.java:90)
        at org.jboss.serial.persister.RegularObjectPersister.writeData(RegularObjectPersister.java:62)
        at org.jboss.serial.objectmetamodel.ObjectDescriptorFactory.describeObject(ObjectDescriptorFactory.java:276)
        at org.jboss.serial.objectmetamodel.DataContainer$DataContainerDirectOutput.writeObject(DataContainer.java:206)
        at org.jboss.serial.persister.RegularObjectPersister.writeSlotWithFields(RegularObjectPersister.java:182)
        at org.jboss.serial.persister.RegularObjectPersister.defaultWrite(RegularObjectPersister.java:90)
        at org.jboss.serial.persister.RegularObjectPersister.writeData(RegularObjectPersister.java:62)
        at org.jboss.serial.objectmetamodel.ObjectDescriptorFactory.describeObject(ObjectDescriptorFactory.java:276)
        at org.jboss.serial.objectmetamodel.DataContainer$DataContainerDirectOutput.writeObject(DataContainer.java:206)
        at org.jboss.serial.persister.RegularObjectPersister.writeSlotWithFields(RegularObjectPersister.java:182)
        at org.jboss.serial.persister.RegularObjectPersister.defaultWrite(RegularObjectPersister.java:90)
        at org.jboss.serial.persister.RegularObjectPersister.writeData(RegularObjectPersister.java:62)
        at org.jboss.serial.objectmetamodel.ObjectDescriptorFactory.describeObject(ObjectDescriptorFactory.java:276)
        at org.jboss.serial.objectmetamodel.DataContainer$DataContainerDirectOutput.writeObject(DataContainer.java:206)
        at org.jboss.serial.persister.ArrayPersister.saveObjectArray(ArrayPersister.java:110)
        at org.jboss.serial.persister.ArrayPersister.writeData(ArrayPersister.java:101)
        at org.jboss.serial.objectmetamodel.ObjectDescriptorFactory.describeObject(ObjectDescriptorFactory.java:276)
        at org.jboss.serial.objectmetamodel.DataContainer$DataContainerDirectOutput.writeObject(DataContainer.java:206)
        at org.jboss.serial.io.JBossObjectOutputStream.writeObjectOverride(JBossObjectOutputStream.java:181)
        at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:298)
        at org.jboss.serial.io.MarshalledObject.<init>(MarshalledObject.java:51)
        at org.jboss.ejb3.stateful.StatefulBeanContext.writeExternal(StatefulBeanContext.java:857)
        at org.jboss.serial.persister.ExternalizePersister.writeData(ExternalizePersister.java:58)
        at org.jboss.serial.objectmetamodel.ObjectDescriptorFactory.describeObject(ObjectDescriptorFactory.java:276)
        at org.jboss.serial.objectmetamodel.DataContainer$DataContainerDirectOutput.writeObject(DataContainer.java:206)
        at org.jboss.serial.io.JBossObjectOutputStream.writeObjectOverride(JBossObjectOutputStream.java:181)
        at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:298)
        at org.jboss.ejb3.cache.simple.StatefulSessionFilePersistenceManager.passivateSession(StatefulSessionFilePersistenceManager.java:390)
        ... 2 more

i can see that it has got to do something with a serializatio. But i dont understand what is wrong. Can any one please help ?
Please note i am new to seam :)

it is happening with seam 2.0.2 and jboss 4.2.3GA