Critical Description
Currently we require several caches to share one instance of persistence store if they participate in a cache-cross transaction (exception is thrown if this requirement is violated). This limitation can be safely removed. sessionEnd callback should be called on all participating stores. These stores will have to properly manage transactions, so this behavior should be properly documented.
We also should provide convenient adapters for JDBC, Spring and Hibernate that will handle transaction management - it doesn't really depend on user's business logic.