The Open Relay Database is shutting down, as “Our volunteer staff has been pre-occupied with other aspects of their lives. In addition, the general consensus within the team is that open relay RBLs are no longer the most effective way of preventing spam from entering your network as spammers have changed tactics in recent years, as have the anti-spam community.”
My only comment? Good. Open relay RBLs had their use years ago, but even then generated false positives. They’re useless now.