tapestry hibernate problem

[T. Papke]

Hi,

i have tried the tapestry-hibernate package to handle my hibernate 
sessions. I have setup the package in maven and add the hibernate 
Session to all constructors of my services.

I started with my CustomerService getting and setting my customerbeans 
(each of them having a Set of AddressBeans). After first time saving a 
customer, everything works fine. If i do the saveOrUpdate again in a 
second request (because i want to change something), i got:
/*"Illegal attempt to associate a collection with two open sessions"*/

I googled a lot, but i do not find the answer??
I thought the tapestry-hibernate module open one session per request? It 
seems so that the session from the previous request is still open?

*service -->*
   public class CustomerFactoryImpl implements CustomerFactory{
       private Session hibernateSession = null;
       public CustomerFactoryImpl(Session session){
           this.hibernateSession=session;
       }
        public void setCustomer(Customer customer) {
           hibernateSession.saveOrUpdate(customer);
       }
    }
*page -->*
   public class CustomerData {
       @Inject
       private CustomerFactory customerFactory;
       @ApplicationState
       private Customer _customer;
  
       public void onSuccess(){
           customerFactory.setCustomer(_customer);
        }
       ....
   }
*bean --->*
   @Entity
   public class Customer{
       @Id
       @GeneratedValue
       private long id;
       ... lots of simple attributes ....
       @OneToMany
       @Cascade(CascadeType.ALL)
       private Set<Address> address= new HashSet<Address>();
       .... access methods to addresses ...
   }

It seems so simple, but i don't know whats going wrong? Anyone an idea?

Thanks a lot,
Thomas