MIME::Lite how to avoid wide character in subroutine for quoted/printable?

[PerlBroker]

I work under strict and warnings. And I get this error: Wide character in subroutine entry at /usr/local/share/perl/5.10.0/MIME/Lite.pm line 2259., referer: Although I check for all arguments to be UTF-8, and they are utf8::valid, the error appears again and again. The $message does not arrive, but $name, $subject work fine. $message = 'ćžćššš' (UTF-8) and it comes from CGI.pm input. Anyone knows how to avoid correctly wide character in print in this case? This is the code:

sub message {
    my ($email, $from, $name, $message, $domain, $referer) = @_;
    $message .= qq{\n\n---\nYour free service at http://example.com\n}
+;
    utf8::decode($message);
    utf8::upgrade($message);
    utf8::decode($name);
    utf8::upgrade($name);
    $from = "=?UTF-8?B?" . encode_base64(encode("utf8", qq{"$name"}), 
+"") . "?= <$from>";
    my $subject = "New  message from $referer";
    $subject = "=?UTF-8?B?" . encode_base64(encode("utf8", qq{$subject
+}), "") . "?=";
    utf8::decode($subject);
    utf8::upgrade($subject);
    my $msg = MIME::Lite->new(
        From    => $from,
        To      => "$email",
        Subject => $subject,
        Type    => 'multipart/related'
    );
    $msg->attach(
        Type    => 'text/plain; charset=UTF-8',
        Data    =>  $message,
        Encoding => "quoted-printable" );
    $msg->attr("content-type.charset"   => 'UTF8');
    $msg->send;
    page("Message sent. Thank you", qq{<p>Thank you very much. Your me
+ssage has been sent.<br/><br/>Go back to: <a href="$referer">$referer
+</a>});
}

[ikegami]

The documentation isn't clear on whether it expects text or bytes (i.e. encoded text) for each header and for messages. The following basic code gives the warning, indicating it wants the text to be encoded for at least some of them:

#!/usr/bin/perl -w

use strict;
use warnings;

use MIME::Lite qw( );

my $addr = '...@....com';

sub message {
    my ($to_name, $to_addr, $fr_name, $fr_addr, $subject, $body) = @_;
    my $msg = MIME::Lite->new(
        From    => qq{"$fr_name" <$fr_addr>},
        To      => qq{"$to_name" <$to_addr>},
        Subject => $subject,
        Type    => 'multipart/related',
    );
    $msg->attach(
        Type     => 'text/plain; charset=UTF-8',
        Data     => $body,
        Encoding => 'quoted-printable',
    );
    $msg->send;
}

message(  # Control
    'a', $addr,
    'a', $addr,
    'a',
    'a',
);

message(  # Test
    "\x{2660}", $addr,
    "\x{2660}", $addr,
    "\x{2660}",
    "\x{2660}",
);

The documentation says it handle MIME encoding already, so all we should have to do is the character encoding.

sub message {
    my ($to_name, $to_addr, $fr_name, $fr_addr, $subject, $body) = @_;

    my $fr = qq{"$fr_name" <$fr_addr>};
    my $to = qq{"$to_name" <$to_addr>};

    utf8::encode( $_ ) for $to, $fr, $subject, $body;

    my $msg = MIME::Lite->new(
        From    => $fr,
        To      => $to,
        Subject => $subject,
        Type    => 'multipart/related',
    );
    $msg->attach(
        Type     => 'text/plain; charset=UTF-8',
        Data     => $body,
        Encoding => 'quoted-printable',
    );
    $msg->send;
}

The warning is gone, and the message displays fine, but looking at the raw email shows that the From, To and Subject fields aren't MIME-encoded. I guess we'll have to do that too.

sub message {
    my ($to_name, $to_addr, $fr_name, $fr_addr, $subject, $body) = @_;

    $_ = encode('MIME-Header', $_)
        for $to_name, $fr_name, $subject;

    utf8::encode( $body );

    my $msg = MIME::Lite->new(
        From    => qq{"$fr_name" <$fr_addr>},
        To      => qq{"$to_name" <$to_addr>},
        Subject => $subject,
        Type    => 'multipart/related',
    );
    $msg->attach(
        Type     => 'text/plain; charset=UTF-8',
        Data     => $body,
        Encoding => 'quoted-printable',
    );
    $msg->send;
}

And bingo!