The challenge is that the end of the last Thursday of March ("Mar lastThu 24:00") isn't always the same thing as the start of the last Friday of March ("Mar lastFri 0:00")--consider, for example, a year in which March 31 falls on a Thursday. Given how Jordan defines its transitions, the "24:00" is necessary here. --ado From: tojo.mathew@nokia.com [mailto:tojo.mathew@nokia.com] Sent: Friday, April 23, 2010 3:13 To: tz@lecserver.nci.nih.gov Subject: Time format error in Olson TZ rules for Asia Hello, We have noticed a possible error in Jordan rule. It uses time value 24:00 in recent updates of Olson rule files. Rule Jordan 2002 max - Mar lastThu 24:00 1:00 S As per RFC 3339,( Clause :5.6. Internet Date/Time Format) it recommends time format from 00-23 for hours. (http://www.ietf.org/rfc/rfc3339.txt ) This implies Jordan rule may need to be changed to: Rule Jordan 2002 max - Mar lastFri 0:00 1:00 S Please check this and update in subsequent releases if found appropriate. Regards, Tojo Mathew Senior Engineer,Application S/W Nokia