Unusually I cannot find anything on the web refering to this issue so I am at a loss as to a starting point to try and understand what is going on.

I am using 7.1.1.Final, Eclipse Indigo (windows), JBoss Tools 3.3.3

So the situation I have two Entity Beans Activity and Resource there are two ManyToMany associations between Activity and Resource.  Prior to adding these associations the JPA archive deployed and executed as expected so I am sure (mostly) that it is the introduction of these two new associations that is causing the problem.

The Activity class is the owner of both of the associations

@Entity    (name="Activity")
@Table    (name="Activity", schema="Istana")
public class JpaActivity
    implements Activity, Serializable
{

    private        String            m_oid;
   
    private        List<Resource>    m_consumers;
   
    private        List<Resource>    m_producers;

    @Column        (name="oid")
    @Id
    @Override
    public         String             getOid()
    {
        return m_oid;
    }
   
    protected    void            setOid(String oid)
    {
        m_oid = oid;
    }

    @ManyToMany    (targetEntity=JpaResource.class,cascade=CascadeType.ALL)
    @JoinTable    (name="activity_consumer_resource"
                ,joinColumns={@JoinColumn(name="activity_oid",referencedColumnName="oid")}
                ,inverseJoinColumns={@JoinColumn(name="resource_oid",referencedColumnName="oid")}
                )
    @Override
    public         List<Resource>     getConsumers()
    {
        return m_consumers;
    }

    protected    void            setConsumers(List<Resource> consumers)
    {
        m_consumers = consumers;
    }

    @ManyToMany(targetEntity=JpaResource.class,cascade=CascadeType.ALL)
    @JoinTable    (name="activity_producer_resource"
                ,joinColumns={@JoinColumn(name="activity_oid",referencedColumnName="oid")}
                ,inverseJoinColumns={@JoinColumn(name="resource_oid",referencedColumnName="oid")}
                )
    @Override
    public         List<Resource>     getProducers()
    {
        return m_producers;
    }

    protected    void            setProducers(List<Resource> producers)
    {
        m_producers = producers;
    }

}

@Entity    (name="Resource")
@Table    (name="Resource", schema="Istana")
abstract
public class JpaResource
    implements Resource, Serializable
{

    private        String            m_oid;
    
    private        Set<Activity>            m_consumerActivitys;
   
    private        Set<Activity>            m_producerActivitys;
   
    @Column        (name="oid")
     @Id
     @Override
     public         String             getOid()
     {
         return m_oid;
     }
    
     protected    void            setOid(String oid)
     {
         m_oid = oid;
     }

    @ManyToMany    (targetEntity=JpaActivity.class,fetch=FetchType.EAGER,mappedBy="consumers")
    @Override
    public         Set<Activity>         getConsumerActivitys()
    {
        return m_consumerActivitys;
    }
   
    protected    void                setConsumerActivitys(Set<Activity> consumerActivitys)
    {
        m_consumerActivitys = consumerActivitys;
    }

    @ManyToMany    (targetEntity=JpaActivity.class,fetch=FetchType.EAGER,mappedBy="producers")
    @Override
    public         Set<Activity>         getProducerActivitys()
    {
        return m_producerActivitys;
    }
   
    protected    void                setProducerActivitys(Set<Activity> producerActivitys)
    {
        m_producerActivitys = producerActivitys;
    }
}

When I attempt to execute the following "Select a FROM Activity a" I get the following stack dump

Exception in thread "main" java.lang.reflect.UndeclaredThrowableException
    at $Proxy0.getActivitys(Unknown Source)
    at com.istana.schedule.session.jee.JeeManager.getActivitys(JeeManager.java:54)
    at com.istana.schedule.session.sui.ActivityPanel.init(ActivityPanel.java:45)
    at com.istana.schedule.session.sui.ActivityPanel.<init>(ActivityPanel.java:40)
    at com.istana.schedule.session.sui.Main.createPage(Main.java:34)
    at com.istana.panticon.client.sui.SuiSiteFactory.createSite(SuiSiteFactory.java:28)
    at com.istana.schedule.session.sui.Main.main(Main.java:50)
Caused by: java.io.EOFException: Read past end of file
    at org.jboss.marshalling.SimpleDataInput.eofOnRead(SimpleDataInput.java:126)
    at org.jboss.marshalling.SimpleDataInput.readUnsignedByteDirect(SimpleDataInput.java:263)
    at org.jboss.marshalling.SimpleDataInput.readUnsignedByte(SimpleDataInput.java:224)
    at org.jboss.marshalling.river.RiverUnmarshaller.doReadObject(RiverUnmarshaller.java:209)
    at org.jboss.marshalling.river.RiverUnmarshaller.readFields(RiverUnmarshaller.java:1677)
    at org.jboss.marshalling.river.RiverUnmarshaller.doInitSerializable(RiverUnmarshaller.java:1593)
    at org.jboss.marshalling.river.RiverUnmarshaller.doInitSerializable(RiverUnmarshaller.java:1557)
    at org.jboss.marshalling.river.RiverUnmarshaller.doReadNewObject(RiverUnmarshaller.java:1235)
    at org.jboss.marshalling.river.RiverUnmarshaller.doReadObject(RiverUnmarshaller.java:272)
    at org.jboss.marshalling.river.RiverUnmarshaller.doReadObject(RiverUnmarshaller.java:209)
    at org.jboss.marshalling.river.RiverUnmarshaller.readFields(RiverUnmarshaller.java:1677)
    at org.jboss.marshalling.river.RiverUnmarshaller.doInitSerializable(RiverUnmarshaller.java:1593)
    at org.jboss.marshalling.river.RiverUnmarshaller.doReadNewObject(RiverUnmarshaller.java:1235)
    at org.jboss.marshalling.river.RiverUnmarshaller.doReadObject(RiverUnmarshaller.java:272)
    at org.jboss.marshalling.river.RiverUnmarshaller.doReadObject(RiverUnmarshaller.java:209)
    at org.jboss.marshalling.river.RiverUnmarshaller.doReadCollectionObject(RiverUnmarshaller.java:180)
    at org.jboss.marshalling.river.RiverUnmarshaller.readCollectionData(RiverUnmarshaller.java:771)
    at org.jboss.marshalling.river.RiverUnmarshaller.doReadObject(RiverUnmarshaller.java:649)
    at org.jboss.marshalling.river.RiverUnmarshaller.doReadObject(RiverUnmarshaller.java:209)
    at org.jboss.marshalling.AbstractObjectInput.readObject(AbstractObjectInput.java:37)
    at org.jboss.ejb.client.remoting.MethodInvocationResponseHandler$MethodInvocationResultProducer.getResult(MethodInvocationResponseHandler.java:107)
    at org.jboss.ejb.client.EJBClientInvocationContext.getResult(EJBClientInvocationContext.java:270)
    at org.jboss.ejb.client.TransactionInterceptor.handleInvocationResult(TransactionInterceptor.java:47)
    at org.jboss.ejb.client.EJBClientInvocationContext.getResult(EJBClientInvocationContext.java:272)
    at org.jboss.ejb.client.ReceiverInterceptor.handleInvocationResult(ReceiverInterceptor.java:132)
    at org.jboss.ejb.client.EJBClientInvocationContext.getResult(EJBClientInvocationContext.java:260)
    at org.jboss.ejb.client.EJBClientInvocationContext.awaitResponse(EJBClientInvocationContext.java:399)
    at org.jboss.ejb.client.EJBInvocationHandler.doInvoke(EJBInvocationHandler.java:140)
    at org.jboss.ejb.client.EJBInvocationHandler.doInvoke(EJBInvocationHandler.java:121)
    at org.jboss.ejb.client.EJBInvocationHandler.invoke(EJBInvocationHandler.java:104)
    ... 7 more
Caused by: an exception which occurred:
    in field storedSnapshot
    in object of type org.hibernate.collection.internal.PersistentBag
    in field m_consumers
    in object of type com.istana.schedule.feature.jpa.JpaActivity
    in element at index [0] of size [4]

Note I have [4] Activity records in the database and the stack dump occurs when calling and returning the [0] Activity and presumeably the persistence manager is attempting to initialise the m_consumers field in Activity via the setConsumers() method.  The return error is "Caused by: java.io.EOFException: Read past end of file" which I assume refers to the ManyToMany association but I am unsure how this relates and/or how I can instrument the application inorder to discover what is really going on.

Some pointer, hints, or scrying would be muchly appreciated.