bad category -- should be "email"

Perhaps related to 0010200

Maybe the difference in the mail headers gives a hint:
In my 1.2.0a3 installation I see

X-Priority: 3

X-Mailer: PHPMailer (phpmailer.codeworxtech.com) [version 2.3]
keywords: ...
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Content-Type: text/plain; charset="utf-8"

In my old 1.0.6 installation I have

X-Priority: 3

X-Mailer: PHPMailer [version 1.72]
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Content-Type: text/plain; charset="windows-1252"

I assume that the charset my have impact.
What also bothers me a little is the difference in the phpmailer version (both mantis installations are operated on the same apache)

Changing core/email_api.php L816 as

$mail->CharSet = $t_email_data->metadata['charset'];
$mail->CharSet = "windows-1252";

Now another experiment:

changin core/email_api.php L901:

function make_lf_crlf( $p_string ) {

$t_string = str_replace( "\n", "\r\n", $p_string );
return str_replace( "\r\r\n", "\r\n", $t_string );
#

$t_string = str_replace( "\n", "", $p_string );

return str_replace( "\r", "", $t_string );

}

gives

Project:                    Remote GraphicsIssue ID:                  

2245Category:                   BasissoftwareReproducibility:           
N/ASeverity:                   minorPriority:                   normalStatus:

I cannot reproduce this. A recent notification from this MantisBT instance:

======================================================================
Project: mantisbt
Meldingsnummer: 10284
Categorie: localization
Reproduceerbaarheid: altijd
Impact: klein
Prioriteit: normaal
Status: nieuw
======================================================================

Header information:

From: Mantis Bug Tracker noreply@mantisbt.org
Subject: [mantisbt 0010284]: Language auto-detection error
Message-ID: 62dcaa641d56646d05fc1460657fabd2@www.mantisbt.org
X-Priority: 3
X-Mailer: PHPMailer (phpmailer.codeworxtech.com) [version 2.3]
keywords: [mantisbt] localization
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Content-Type: text/plain; charset="utf-8"

Now I tried my fortune with

/**


select the method to mail by:
PHPMAILER_METHOD_MAIL - mail()
PHPMAILER_METHOD_SENDMAIL - sendmail
PHPMAILER_METHOD_SMTP - SMTP
@global int $g_phpMailer_method

*/

$g_phpMailer_method     = PHPMAILER_METHOD_SENDMAIL;

tk: which mailer method was you using ?

I was using the default (i.e., PHPMAILER_METHOD_MAIL accrding to config_defaults_inc.php)

Resolving as no update for > 3 years and considering PHPMailer has been through several updates now, most likely no longer an issue.