WebObjects/Web Applications/Development/Persistent Sessions

Related question: Does anyone have a good example for how to save an expired session to database, and recreate it after it expires?

Nope, but perhaps take you could look at /Developer/Examples/JavaWebObjects/PersistentSessionStore.

From the readme file: The PersistentSessionStore application demonstrates one possible alternative session store object -- WXPersistentSessionStore. In WebObjects, the session store is the object that handles the storage of your session state between requests. The default session store is the ServerSessionStore, but that only stores the session while the app is running and cannot deal with interruptions in service and consumes virtual memory. The persistent session store solves these problems by putting the session on disk as a backup in the event the app dies or the in-memory session times out.