sub str2epoch {
    my( $d, $m, $y, $H, $M, $S, $tz ) = $_[0] =~
        m/^.... (\d\d) (...) (\d\d\d\d) (\d\d):(\d\d):(\d\d) ([+-]\d{4})/
        or die "Bad format $_[0]";
        
    my $leaps =  int( ($y - 1970) / 4 + 0.5 );
    (((($y-1970)*365 +$leaps+MONTHS->{$m}+($d-1))*24 +$H)*60 +$M)*60 +$S
              - ($tz < 0 ? -1 : 1)*(substr($tz,1,2)*3600 + substr($tz,3)*60);
}