DateTime works fine for me. (undef, epoch, 1301690690) isn't the correct way to do it. I did this using now and from_epoch:

#!/usr/bin/perl 

use strict;
use warnings;
use DateTime;

my $dt = DateTime->now( 'time_zone' => 'local' )
   ->set_time_zone( 'floating' );
print $dt, "\n";

$dt = DateTime->from_epoch( 'epoch' => 1301690690 );
print $dt, "\n";
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