From this morning's updates on ubuntu.
Version 2009n-0ubuntu0.9.04.1:
* Add argentinas-dst-2009.diff: Disable DST switch for Argentina tomorrow,
as the Argentina government decided yesterday. Careful planning is boring.
Thanks to Margarita Manterola for the patch! (LP: #453165)
I find timezones fascinating, especially how much they get messed with for no particularly justifiable reason.