Some of the implications of section 11.4 don't appear to be checked for in the case of an already-closed PersistenceManagerFactory.
1. If close() is called on an already-closed PMF (with correct permission i.e. "closePersistenceManagerFactory"), no exception should be thrown.
2. If close() is called on an already-closed PMF (without correct permission), exception should be thrown (even though it would otherwise do nothing).
3. If close() fails (throws JDOUserException) due to active transaction(s), then none of the PersistenceManager objects belonging to the PMF should have actually been closed.
4. Several get/set pairs are not tested for their behaviour after close()