Vi riporto questo messaggio di Minisini apparso nella M.L. ufficiale:
" Since revision #6273, System.TimeZone now takes the daylight saving time into account.
It's not technically the timezone anymore, but I can't change the property name.
And concretely daylight saving time changes your timezone after all.
Knowing the current daylight saving time needs a GNU C library extension coming from BSD.
--
Benoît Minisini "