History reset

Resently I started to get this alert that says my History needs to be reset. Owner and permissions of the HIstory.db seems to be okay. I use SpamSieve 2.6.6 with PowerMail 5.6.3 on a MacBook Pro 2.2 GHz w/ Mac OS 10.4.11

Most likely, the problem is with the contents of the database file rather than its permissions.