1. Allow multiple fields (properties) to be used for ordering persistent Lists or Maps.

   2. Specify the behavior at flush time if the user has inserted elements or entries out of order in ordered fields (properties).

   3. Allow the user to create fetch groups dynamically.

   4. Require SingleFieldIdentity classes to implement Comparable so they can be used in non-persistent ordered Set or Map instances.

   5. Add ReadOnly to PersistenceManagerFactory to allow fail-fast on applications that use a read-only data store.

   6. Provide a way to specify the isolation level of connections used for a PersistenceManagerFactory.

   7. Add an invocation API for a run-time enhancer. This allows for a standard command-line tool and standard IDE plugins for enhancement.

   8. Require a no-args constructor for implementations of PersistenceManagerFactory and add the getPersistenceManagerFactory... methods to the PersistenceManagerFactory interface. This change allows JDOHelper to use Java 6 ServiceLoader in future.