Truthfully no. I've long since given up trying to figure out the "why's" behind such things, I just play with stuff till I get it to work:)

The whole area of timezones seems to be pretty mixed up, even outside of MS doing everything their own way. I've no idea what GST and GDT stand for; maybe G... Summer Time and G... Daylightsaving Time?

I thought that the 1 in the middle meant "add one hour" for that period of time when the second part of the string is in force, but empirically it appears to be the opposite?

c:\>set TZ=GMT1GMT

c:\>perl -le"print ~~localtime;" & time /t
Tue Sep 14 17:44:24 2004
18:44

c:\>set TZ=GMT-1GMT

c:\>perl -le"print ~~localtime;" & time /t
Tue Sep 14 19:44:34 2004
18:44
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