HibernateException: this instance does not yet exist as a ro

[wmax]

I have a stateful session bean that uses other stateless session beans via their remote interfaces. The stateless session beans use EJB3 persistence. Now I have this scenario:

Application bean (stateful):

Resource resource = securityManager_.createResource(admin);
return folderManager_.createRootFolder(resource);

Security Manager bean (stateless):

@PersistenceContext private EntityManager em_;

public Resource createResource(User owner) throws SecurityException {
 Resource resource = new Resource(owner);
 em_.persist(resource);
 return resource;
}

Folder Manager bean (stateless):

@PersistenceContext private EntityManager em_;

public Folder createRootFolder(Resource resource) throws FolderException {

 // this instruction causes the exception
 em_.refresh(resource);

 // code omitted
}

The em_.refresh(resource); causes a HibernateException to be throws:

Stack Trace:
* org.hibernate.ejb.AbstractEntityManagerImpl.throwPersistenceException(AbstractEntityManagerImpl.java:567)
* org.hibernate.ejb.AbstractEntityManagerImpl.refresh(AbstractEntityManagerImpl.java:239)
* org.jboss.ejb3.entity.TransactionScopedEntityManager.refresh(TransactionScopedEntityManager.java:193)
* net.sf.adigres.foldermanager.FolderManagerBean.createRootFolder(FolderManagerBean.java:88)
* ....
Caused by: org.hibernate.HibernateException: this instance does not yet exist as a row in the database
* org.hibernate.event.def.DefaultRefreshEventListener.onRefresh(DefaultRefreshEventListener.java:90)
* org.hibernate.event.def.DefaultRefreshEventListener.onRefresh(DefaultRefreshEventListener.java:39)
* org.hibernate.impl.SessionImpl.fireRefresh(SessionImpl.java:895)
* org.hibernate.impl.SessionImpl.refresh(SessionImpl.java:879)
* org.hibernate.ejb.AbstractEntityManagerImpl.refresh(AbstractEntityManagerImpl.java:233)
* ... 106 more

This happens only in conjunction with the stateful Application bean. Stand alone tests of the two stateless beans involved work without problems.

I guess it has something to do with transactions but I don't use @TransactionAttribute annotations anywhere so the default value (REQUIRED) should apply (and be appropriate).

Can anyone help me with this, please?

[wmax]

Correction: I have a stateful session bean that uses other stateless session beans via their local interfaces.

... but it makes no difference.