[Vala] HELP GLib.DateTime (TimeZone = 0) on Windows

[Edwin DLCA <edwinspire gmail com>]

Again I seek your help.
I wrote something very small to get the date and time and print it on
console.
Thus:

    GLib.DateTime Fechi = new GLib.DateTime.now_utc();
    stdout.printf (">>> %s \n", Fechi.format("%F %H:%M:%S"));
    stdout.printf (">>> %s \n", Fechi.to_string());

The result is correct when you compile in Linux.
> > > 06/09/2011 16:07:59
> > > 2011-06-09T16 :07:59 - 500

But when I compile in Windows get
> > > 06/09/2011 21:07:59
> > > 2011-06-09T21 :07:59 - 000

This is not correct, my PC samples the 16:07 not 21:07.
I understand to be a problem with TimeZone but not how to change it, I
thought to compile the same code on linux and windows the result would be the
same, but this is not the case.
I searched google but can not find any solution.
Thank you for your help.