my $mailer = GT::Mail->new(
'header_charset' => 'ISO-8859-2'
);

$mailer->args(
'header_charset' => 'ISO-8859-2'
);

use strict;
use warnings;

use Data::Dumper;
use GT::Mail;


# Get a new mailer object
my $mailer = GT::Mail->new(
# 'header_charset' => 'ISO-8859-2'
);

#$mailer->args(
# 'header_charset' => 'ISO-8859-2'
#);

$mailer->set('header_charset', 'ISO-8859-2');

# Input a text email string, with full header
my $mail_txt = q|To: Hisname <info@hisdomain.com>
From: Myname <me@mydomain.com>
Errors-To: Hisname <info@hisdomain.com>
Subject: Test email subject - áíûõüöúóé

test email message body - áíûõüöúóé
|;

# Parse the string
$mailer->parse($mail_txt);

# Flatten mail object into string
my $mail_result = $mailer->as_string();
print '$mail_result: ' . Dumper(\$mail_result) . "";

my $mailer = GT::Mail->new(
'mail_charset' => 'ISO-8859-2'
);

my $mailer = GT::Mail->new(
'header_charset' => 'ISO-8859-1'
'body_charset' => 'ISO-8859-2'
);

use strict;
use warnings;

use Data::Dumper;
use GT::Mail;


# Input a text email string, with full header
my $mail_txt = q|To: áéóöõúüûí <to@email.com>
From: áéóöõúüûí <from@email.com>
Errors-To: áéóöõúüûí <from@email.com>
Subject: Test - áéóöõúüûí

Test - áéóöõúüûí
|;


my $top = GT::Mail::Parse->new(
in_string => $mail_txt,
crlf => "\n",
headers_intact => 0,
)->parse();

my $charset = $top->delete('GT-Header-Charset');
$top->{header_charset} = $charset if $charset;

my $mail = new GT::Mail;
$mail->top_part($top);

# Flatten mail object into string
my $mail_result = $mail->as_string();
print '$mail_result: ' . Dumper(\$mail_result) . "";