Comment 1 for bug 1001340

After some searching, the problem is most probably that the time zone name returned from the windows registry.by GetTimeZoneInformation() is a) non-standard and b) localized. You could probably scan the subkeys of HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Time Zones until you find one whose Std or Dlt value is equal to the GetTimeZoneInformation() result (not necessarily identical to the subkey name!). Then parse the TZI value of the same entry for the appropriate bias'es (cf http://www.pcmag.com/article2/0,1895,1166624,00.asp for format info), and use the computed bias as +|-nn:nn.