Yesterday we released an update to accommodate daylight saving time (DST) changes in several countries.
We recommend that customers deploy the most current Windows cumulative time zone update to guarantee the consistency of the time zone database on all systems.
The update that this article describes changes the time zone data to accommodate daylight saving time (DST) changes in several countries, as outlined in this article. This update also includes other DST-related changes, time zone-related changes, and settings-related changes.
The full article detailing the updates and links to the downloads are available here – http://support.microsoft.com/kb/951072