I'm sure it is, I just don't know what it is off hand.
However I have remembered that some programming languages have (at least in past versions I have used) not allowed for DST.
If you want it automatically I suppose you could set the series of dates that is DST and add the hour and then set a series of date it is normal GMT. This would involve some kind of If statement but would be harder to implement.
I will keep a look out for some more information on it for you.
Hope that helps
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