This morning, I noticed emails where going into the spam folder, for no good reason. It seems this rule triggers, from 72_active.cf:

header   FH_DATE_PAST_20XX    Date =~ /20[1-9][0-9]/ [if-unset: 2006]

Unless I complete missunderstand this, this means 2010 is considered a too futuristic date. Clearly not good. For now, I simply disabled this rule, by adding this to my local.cf file:

score FH_DATE_PAST_20XX 0

I probably should fix the regex above, but I have no idea what weight that should have now, so I figure it's better to just turn this rule off entirely.