Just found it on the Admin Guide on Roll-forward Recovery. Very, very nice.

De: Néstor Boscán [mailto:nestor.boscan@tcs.com.ve]
Enviado el: Jueves, 27 de Diciembre de 2007 06:49 p.m.
Para: 'Derby Discussion'
Asunto: How to use Backup and Log files to recover a Derby Database?

I need to be able to recover my Derby database to the last transaction, even if the disk is corrupted. Is there a way I can tell Derby to do a backup and log all transaction since my backup on a different disk so I can recover the database? I know Derby uses logs and I can also backup a database. But I read that the logs are deleted in every checkpoint.
Néstor Boscán