I'm trying to create a Tk app with multiple list boxes. The problem is when I select an item from one box it automatically deselects the items from the other. What am I doing wrong?

Thanks Monks!!!

#!/usr/bin/perl -w

use strict;
use warnings;
use Tk;


my $mw = MainWindow->new;
my $frame = $mw->Frame->pack(-side => 'top', -fill => 'x');


my $box1 = $mw->Scrolled("Listbox", -scrollbars => 'osoe',
                                         -height => 10,
                                         -selectmode => "multiple")->p
+ack(-fill => 'x');

my $box2 = $mw->Scrolled("Listbox", -scrollbars => 'osoe',
                                         -height => 10,
                                         -selectmode => "multiple")->p
+ack(-fill => 'x');

#test data
for my $x (1..100) {
        $box1->insert('end', $x);
        $box2->insert('end', $x);
}

MainLoop;
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