Bangladesh is applying DST this 20.th.of June. In file tzdata2009i this is the attempt to implement it: Rule Bang 2009 only - Jan 1 0:00 0 - Rule Bang 2009 only - Jun 20 0:00 1:00 S Now that doesn't make sense to me at all. Bangladesh has not had anything close to "DST" since 1951, and then we zero-set DST January 1st. 2009? Then after implementation of DST next Saturday we leave it dangling for the next millenium? Probably this is really just a "typo" for Rule Bang 2010 only - Jan 1 0:00 0 - Rule Bang 2009 only - Jun 20 0:00 1:00 S So Bangladesh leaves DST with year end of 2009, since we have no authoritative information. But this is not a very good guess in my opinion, in fact Steffen Thorsen mentions semi-authoritative information: "On another note, Bangladesh's minister for power said earlier in 2009 that the new timing might continue until the end of September. Timeanddate.com will provide an update on the DST end date when it becomes available." Any guess in the end of September seems better to me, or October 1.st. 2009 at 0:00? ... perhaps this was why Dave Rolsky's test cases were blowing up? :) - Jesper Nørgaard Welen