{
my %cache;
sub cache {
    my $str = shift;

    my ($wday, $mon, $mday, $time, $year) = split /\s+/, $str;
    my ($hour, $min, $sec)                = split ':',   $time;

    my $timebase;

    if ($cache{"$year$mon$mday"}) {
        $timebase = $cache{"$year$mon$mday"};
    } else {
        $timebase = timelocal(0, 0, 0, $mday, $mtrans{$mon}, $year-1900);
        $cache{"$year$mon$mday"} = $timebase;
    }

    return $timebase + $sec + $min*60 + $hour*60*60;
}
}