Mike Cardwell, an IT consultant in Nottingham, UK, reported on his blog finding a Y2010 bug in Spam Assassin. He found an error in a rule that Spam Assassin folks thought they fixed.

“I think a lot of systems will be experiencing false positives on their ham because of this at the moment. It is a particularly high scoring rule considering that the default threshold is 5.0,” he wrote.

For further information see: SpamAssassin Rule: FH_DATE_PAST_20XX