sub timegm {
    my ($sec,$min,$hour,$mday,$month,$year) = @_;

    if ($year >= 1000) {
    $year -= 1900;
    }
    elsif ($year < 100 and $year >= 0) {
    $year += ($year > $Breakpoint) ? $Century : $NextCentury;
    }

    unless ($Options{no_range_check}) {
    if (abs($year) >= 0x7fff) {
        $year += 1900;
        croak "Cannot handle date ($sec, $min, $hour, $mday, $month, *$year*)";
    }

    croak "Month '$month' out of range 0..11" if $month > 11 or $month < 0;

    my $md = $MonthDays[$month];
#        ++$md if $month == 1 and $year % 4 == 0 and
#            ($year % 100 != 0 or ($year + 1900) % 400 == 0);
    ++$md unless $month != 1 or $year % 4 or !($year % 400);

    croak "Day '$mday' out of range 1..$md"   if $mday  > $md  or $mday  < 1;
    croak "Hour '$hour' out of range 0..23"   if $hour  > 23   or $hour  < 0;
    croak "Minute '$min' out of range 0..59"  if $min   > 59   or $min   < 0;
    croak "Second '$sec' out of range 0..59"  if $sec   > 59   or $sec   < 0;
    }

    my $days = _daygm(undef, undef, undef, $mday, $month, $year);
    my $xsec = $sec + $SecOff + 60*$min + 3600*$hour;

    unless ($Options{no_range_check}
        or  ($days > $Min{Day} or $days == $Min{Day} and $xsec >= $Min{Sec})
       and  ($days < $Max{Day} or $days == $Max{Day} and $xsec <= $Max{Sec}))
    {
        warn "Day too small - $days > $Min{Day}\n" if $days < $Min{Day};
        warn "Day too big - $days > $Max{Day}\n" if $days > $Max{Day};
        warn "Sec too small - $days < $Min{Sec}\n" if $days < $Min{Sec};
        warn "Sec too big - $days > $Max{Sec}\n" if $days > $Max{Sec};
    $year += 1900;
    croak "Cannot handle date ($sec, $min, $hour, $mday, $month, $year)";
    }

    no integer;

    $xsec + 86400 * $days;
}