use warnings;
use strict;
use MIME::Parser;

my $email = 'Subject: none';

my $parser = new MIME::Parser;
my $entity = $parser->parse_data ($email) or die "Bad Parse. ";
my $subject = $entity->head->get ('subject', 0);
my $crap = defined $subject?$ entity->head->get ('Subject', 0) : 'unde­f';

print $crap;