As per the announcement from Bangladesh Government, the clock will move 1 hour advance to save on Electricity consumption during evening peak hours. the decision will be effective from 19th June, 2009 11:00 PM. In response to the decision microsoft and other software/hardware vendors has come up with the solutions/patches. You can do it manually by advancing the clock on 19th June 11:oo PM and adjust the time again when the DST is over.
To make the life easier, you can install a tiny little fix to the daylight saving feature here (KB 972423) Size: 640 KB
Note: As the government hasn’t decided the end date of the Daylight saving decision, this patch does not contains end date specified as 31st December, 2009. Microsoft will release another patch after the declaration has been made by the government.