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                --ado
 
-----Original Message-----
From: Mok Ly Yng [mailto:lymok@starhub.net.sg]
Sent: Friday, January 23, 2004 9:01 AM
To: tz@lecserver.nci.nih.gov
Subject: Time Zone: Malaysia & Singapore

Hi there,

I am Mok Ly Yng.  I found my name mentioned in the latest version of the tz data file.  I have added a few other points to the Malaysia and Singapore time zone info.  These are marked in blue.

For both Malaysia and Singapore, for many years in the past versions of this file, the first date was listed as 'Until 1880'.  This was the date which prompted my research into the history of legal time in Singapore and Malaysia.  It turned out that '1880' was the founding year of Kuala Lumpur.  So, it could not have been an 'Until' date.

Kuala Lumpur kept its own Local Mean Time of 6:46:46 until it was changed to Singapore's Mean Time on 01 Jan 1901, along with the rest of the other Malay States under British rule.  The difference of 2 sec between 6:46:46 and 6:46:48 (as in the original version) was probably due to the rounding off of arc seconds in the longitude value.

Singapore was founded in 1819 and had kept different local mean times depending on the different longitude values as determined by different authorities over the years.

The only uncertainty remaining is the WWII years of 1942-1945.  I am still trying to find out the exact dates of time changes.

Regards,

Mok

==========

# @(#)asia      7.73

# Malaysia
# Rule  NAME    FROM    TO      TYPE    IN      ON      AT      SAVE    LETTER/S
Rule    NBorneo 1935    1941    -       Sep     14      0:00    0:20    TS # one-Third Summer
Rule    NBorneo 1935    1941    -       Dec     14      0:00    0       -
#
# peninsular Malaysia
# From Paul Eggert (2003-11-01):
# The data here are taken from Mok Ly Yng (2003-10-30)
# <http://www.math.nus.edu.sg/aslaksen/teaching/timezone.html>.
# Before 1901, Penang, Malacca and Singapore each had their own time zone;
# assume Kuala Lumpur used Malaccan time.
  [This did not happen.  K.L. had its own L.M.T. of 6:46:46 from GMT.]
# Zone  NAME            GMTOFF  RULES   FORMAT  [UNTIL]
Zone Asia/Kuala_Lumpur  6:46:46 -       LMT     1901 Jan  1 # K.L. Local Mean Time
                        6:55:25 -       SMT     1905 Jun  1 # Singapore M.T.
                        7:00    -       MALT    1933 Jan  1 # Malaya Time
                        7:00    0:20    MALST   1936 Jan  1
                        7:20    -       MALT    1941 Sep  1
                        7:30    -       MALT    1942 Feb 16
                        9:00    -       JST     1945 Sep 12
                        7:30    -       MALT    1982 Jan  1
                        8:00    -       MYT     # Malaysia Time


# Singapore
# The data here are taken from Mok Ly Yng (2003-10-30)
# <http://www.math.nus.edu.sg/aslaksen/teaching/timezone.html>.
# Zone  NAME            GMTOFF  RULES   FORMAT  [UNTIL]
Zone    Asia/Singapore  6:55:25 -       LMT     1901 Jan  1 # Local Mean Time
                        6:55:25 -       SMT     1905 Jun  1 # Singapore M.T.
                        7:00    -       MALT    1933 Jan  1 # Malaya Time
                        7:00    0:20    MALST   1936 Jan  1
                        7:20    -       MALT    1941 Sep  1
                        7:30    -       MALT    1942 Feb 16
                        9:00    -       JST     1945 Sep 12
                        7:30    -       MALT    1965 Aug  9 # independence
                        7:30    -       SGT     1982 Jan  1 # Singapore Time
                        8:00    -       SGT