improve performance of session.clear()

Clearing a session that contains a large number of Proxies takes a very long time. The reason for this is that null is set on the LazyInitializer when clearing the StatefulPersistenceContext, whenever a new session is set on an AbstractLazyInitializer, a check is done to see if the AbstractLazyInitializer is still attached to its previous session (and correctly throws an exception if it is). This check performs a linear search through all Proxies in the PersistenceContext. Since we're setting the session to null, do we really need to do this expensive linear search?
I propose we not perform the linear search if the session being set on the AbstractLazyInitializer is null.