Bumping this a bit just to mention that the very same issue is present on User profile -> Seen XXX, where XXX looks nice on small time period (up to weeks), but fails badly on months.
E.g.:
-
Văzut acum 5 zileis ok (seen 5 days ago) -
văzut acum 2 săptămâniis ok (seen 2 weeks ag) -
văzut acum 31 maiis not ok (seen 31 may)
I think this can be solved using a syntax similar to this: Message Format support for localization.