Update: removed the link to the SpamAssassin announcement as the link isn’t permanent! 🙁
Those of you using SpamAssassin to filter your mail may want to watch things a bit more closely than usual; it seems that current versions still include the rule known as FH_DATE_PAST_20XX, which adds 2-3 points to any message with a 2010 date in the headers. Surprisingly enough, such dates have suddenly become common, with the result that SpamAssassin may be generating more false positives than usual.
The fix is now included in the updates pushed out by
sa-update, run it with
-D to get debug output and check you’ve picked up 895075 or later. You’ll see it say:
 dbg: dns: 5.2.3.updates.spamassassin.org => 895075, parsed as 895075
If you’re running Zimbra then you’ll need to fix this manually, in the VPAC install (5.0.x) I changed a line in
header FH_DATE_PAST_20XX Date =~ /20[1-9][0-9]/ [if-unset: 2006]
header FH_DATE_PAST_20XX Date =~ /20[2-9][0-9]/ [if-unset: 2006]
The other alternative is to set the score of the rule to 0 in your
score FH_DATE_PAST_20XX 0.0
Then go hunting for legitimate email in your spam folder (I’m lucky enough that none got picked up).