I live in Chile and the government has decided to go to winter time later than usual a few months ago. Apple has not provided an update for OS X to reflect this change.
I now fixed the timezones manually by downloading timezone files and using zic to update my mac based on instruction found here
http://hints.macworld.com/article.php?story=20070128185822710
The good thing is now that if I set the timezone now to Chile/Santiago in the Date & Time preferences to Santiago/Chile that when I issue the date command in the terminal I get the right time.(still summer time). However all the Mac Clock on the panel and also all Mac Apps are one hour off. They show already winter time.
Any idea on how to get the mac apps show the right time?
Best Answer
OK I found the solution by using instructions found here http://brickybox.com/2009/10/18/os-x-fix-argentina-dst-october-2009
Except the thing I already did with "zic" you also need to update the timezone files for "ICU". The article I refer to is for an older version of OS X. For mountain lion. Download ICU from here: http://www.opensource.apple.com/release/mac-os-x-1082/ and the latest timezone data from http://www.iana.org/time-zones