[Zope] Removing old FileStorage backups from repozo

Hi I'm using the repozo.py script to back up some large FileStorages, as outlined in: http://www.zope.org/Wikis/ZODB/FileStorageBackup I need to clear out old backups regularly, as there are several storages which are packed every night, and so there are lots of ~2G backups files around for every day. Can I just go in and delete files older than X days from the backup directory, or will this upset repozo, which apparently keeps info about its backup files in the .dat file? Thanks, Felix.