Wrong return-path

[As discussed here](https://www.phpbb.com/community/viewtopic.php?f=46&t=2101814), sometimes phpBB sends emails with a wrong return-path. My config:

Actual results:

Authentication-Results: hotmail.com; spf=none (sender IP is 95.141.35.37) smtp.mailfrom=apache@skycracker.zane.it; dkim=pass header.d=turbolab.it; x-hmca=pass header.id=info@turbolab.it

[snip]

To: =?UTF-8?B?WmFuZQ==?= <info@turbolab.it>
Subject: =?UTF-8?B?UHJvdmEgZGkgU0ZQ?=
From: "=?UTF-8?B?VHVyYm9MYWIuaXQ=?=" <info@turbolab.it>
Reply-To: "=?UTF-8?B?VHVyYm9MYWIuaXQ=?=" <info@turbolab.it>
Sender: <info@turbolab.it>

[snip]

Return-Path: apache@skycracker.zane.it

As a workaround, I changed the color=#0000FFfunction phpbb_mail($to, $subject, $msg, $headers, $eol, &$err_msg)[/color] found in includes/functions_messenger.php:

from:

[code]$result = $config['email_function_name']($to, mail_encode($subject, ''), wordwrap(utf8_wordwrap($msg), 997, "\n", true), $headers);[/code]

to:

color=#0000FF$result = $config['email_function_name']($to, mail_encode($subject, ''), wordwrap(utf8_wordwrap($msg), 997, "\n", true), $headers,, "-f" . $config['board_email']);[/color]

This fixed the problem, but I don't want to patch phpBB core like this.

Thanks.