Yeah, some of the encryption modules work better than others. I've had better luck with GnuPG.

#!/usr/bin/perl
use warnings;
use strict;
use GnuPG;

my $gpg = new GnuPG(homedir => '/home/zentara/.gnupg');

$gpg->encrypt(plaintext =>"Gnufile.txt", output => "Gnufile.gpg",
      recipient =>"zentara\@zentara.net",armor=>"1");

exit;
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I did have to fix line 267 of GnuPG.pm, and single quote a string, but after that it worked fine.