use strict;
use warnings;
use Win32::API;
use Win32::API::Struct;
Win32::API::Struct->typedef(LOCALTIME => qw{
   WORD wYear
   WORD wMonth
   WORD wDayOfWeek
   WORD wDay
   WORD wHour
   WORD wMinute
   WORD wSecond
   WORD wMilliseconds
});

Win32::API->Import('kernel32', 'BOOL SetLocalTime(LOCALTIME lpPoint)');
my $localtime = Win32::API::Struct->new('LOCALTIME');

# dann kann man mit $localtime->{wYear} = 2004, etcpp. die Werte setzen
# und dann die Funktion aufrufen

@{$localtime}{qw/wYear wMonth wDay wHour wMinute wSecond wMilliseconds/} = qw/2004 2 10 23 22 30 0/;

SetLocalTime($localtime) or print Win32::FormatMessage Win32::GetLastError;