There is a subtle problem in the Tzdata2009e file about Jordan:
The Council of Ministers decided in 2002 to adopt the principle of timely submission of the summer at 60 minutes as of midnight on the last Thursday of the month of March of each year.
The problem is quite similar to the problem of the San Luis timezone in Argentina. The rule is this time Last Thursday in March at midnight, but has been implemented in 2009e as Last Friday in March, which is not the same. The problem occurs first in 2005, where timeanddate.com starts DST Thursday the 31.st. of March at 23:59:59, while the rules of 2009e will impose DST to start Friday the 25.th. of March 2005 at 0:00. In the tz database there are quite a lot of midnight-rules, however all have been end of DST thus it was possible to say 23:00s instead of 24:00. I wonder if there is a problem making the following definition:
! Rule Jordan 2002 max - Mar lastThu 24:00s 1:00 S If there is, it might be necessary to hand-code the dates where Last Thursday of March is the 31.st.
Regards, Jeser Nørgaard Welen