The December 2011 DST Cumulative update for Windows operating systems has been published on Microsoft Download Center. It contains the following changes:

• Kaliningrad Standard Time:
  As previously announced in KB2625508, Belarus has decided to discontinue daylight saving time from 2011 and stay on permanent ‘summer time’. KB2625508 suggested moving to a ‘workaround time’ of Kaliningrad standard time. This windows update makes the move permanent by including Minsk in the display name for Kaliningrad standard time. The new displayname for Kaliningrad Standard time is “(UTC+03:00) Kaliningrad, Minsk”.
• E.Europe Standard Time :
  The Displayname for this timezone has been updated to “(UTC+2:00) Nicosia”
• Bahia Standard Time [Display Name "(UTC-3:00) Salvador"]:
  A new windows timezone has been created for the Brazilian state of Bahia.
• Fiji Standard Time [Display Name " (UTC+12:00) Fiji"]:
  Sets the 2012 DST start date to occur on the fourth Sunday of January.
• Samoa Standard Time:
  Changes the UTC offset for Samoa Standard time from (UTC-11) to (UTC+13). This results in the timezone’s displayname changing to “(UTC+13:00) Samoa”.

 For more information on these adjustments, refer to this Microsoft KnowledgeBase article:   http://support.microsoft.com/kb/2633952