@Cache(usage = CacheConcurrencyStrategy.READ_WRITE)
@Entity
public class Territory{
..
  @Cache(usage = CacheConcurrencyStrategy.READ_WRITE)
  @OneToMany(mappedBy = "parent")
  public List<Territory> getChildren() {...}

  @ManyToOne(fetch = FetchType.LAZY)
  public Territory getParent(){...}
}
...

int i = persister.getEntityMetamodel().getPropertyIndex( mappedBy );  // PARENT INDEX!
					Serializable oldId = null;
					if ( oldState != null ) {
						// in case of updating an entity we perhaps have to decache 2 entity collections, this is the
						// old one
						oldId = session.getIdentifier( oldState[i] ); // THROWS EXCEPTION BECAUSE PARENT = NULL SO oldState[i] = null too!