Hi All, More on the global sequence subject - you can define such a sequence in persistence.xml like this: Having this, you can annotate your entities with plain @GeneratedValue and your custom sequence will be used. As Kevin mentioned, OpenJPA does not call allocate(), however you can call it from the application: OpenJPAEntityManager kem = OpenJPAPersistence.cast(em); kem.getIdGenerator(TimeUuidEntity.class).allocate(100); Cheers, Milosz