Date/time in terminal correct but one hour off in apps
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