We use this new 'short4' called more european-friendly time format: MM-DD-YY 24:00:
simply make the following additions to w3t.pm / convert_time and check 'short4' in w3ttheme.pm:
(new code between #>>>)

sub convert_time {
...
my ($hour,$min,$sec)=split(/:/,$tarray[3]);

#>>> new $hour24
my $hour24=$hour;
#>>>
...
elsif ($theme{'timeformat'} eq "short3") {
$time="$year/$months{$tarray[1]}/$tarray[2] $hour:$min $AMPM";
}

#>>> new format "short4": MM-DD-YY 24:00
elsif ($theme{'timeformat'} eq "short4") {
if ($months{$tarray[1]}<10) {
$months{$tarray[1]}="0$months{$tarray[1]}";
}
if ($tarray[2]<10) {
$tarray[2]="0$tarray[2]";
}
$time="$months{$tarray[1]}-$tarray[2]-$year $hour24:$min";
}
#>>>
...