I would like implement transactions classes to work with a non-transactional DB. a non-transactional DB could be EXCEL document, for example. the non-transactional DB does have contraints defined and if any of the constraints are violated during a DML operation, the operations that happened prior to the current operation need to be rolled back. I have some custom transaction classes written, however, I do not know how to let hibernate know to use them. The transaction classes are based on plain JDBC transaction implementing javax.transaction.* interfaces