We are using hibernate jpa in combination with spring webflow and when the hibernate session
gets de-serialized we get nullpointers due to the exceptionconverter being null.
The problem seems to be situated in org.hibernate.internal.SessionImpl readObject method which doesn't restore the exceptionConverter field.
Possibly this is a bug due to the way jpa and hibernate are integrated. (non standard)
However just looking at the source code seems like the transient fields should be restored in the readObject method
Alternatively the session shouldn't be serializable but I think that will break much more since third parties probably rely on this feature...