Please attach a screenshot!

this ist the text/plain part of the body of the MIME mail:

Dear j,You, or someone using your email address, have registered to participate in an online survey titled test1.To complete this survey, click on the following URL:http://survey60k.zsi.at/index.php?lang=en&sid=48985&token=8nx3fwbc26dg5stIf you have any questions about this survey, or if you did not register to participate and believe this email is in error, please contact ZSI Survey Admin at survey@zsi.at.

Please upgrade to the latest version and build and tell us, if you can reproduce the issue (no one else reported the issue so far).

I registered myself at your survey and everythink was OK ==> see attached screenshot.

Please provide feedback or we'll close that ticket!

To see the problem you either have to view your mail with MIME type text/plain (which some user prefer to text/html, and which is delivered by PHPmailer as alternative MIME type), or you have to view the source of the mail. The source looks like this:

Return-Path: survey@zsi.at
X-Original-To: simon@zsi.at
Delivered-To: simon@zsi.at
Received: from localhost (localhost.localdomain [127.0.0.1])
by dmail.zsi.at (Postfix) with ESMTP id A5F4D17E950
for simon@zsi.at; Thu, 8 Oct 2009 10:49:14 +0200 (CEST)
X-Virus-Scanned: Debian amavisd-new at dmail.zsi.at
Received: from dmail.zsi.at ([127.0.0.1])
by localhost (localhost.localdomain [127.0.0.1]) (amavisd-new, port 10024)
with ESMTP id UnHegcd7Cirq for simon@zsi.at;
Thu, 8 Oct 2009 10:49:12 +0200 (CEST)
Received: from marduk.zsi.at (marduk.zsi.at [78.46.105.46])
by dmail.zsi.at (Postfix) with ESMTP id 4AF7017E765
for simon@zsi.at; Thu, 8 Oct 2009 10:49:12 +0200 (CEST)
Received: by marduk.zsi.at (Postfix, from userid 33)
id 642BA8C0061; Thu, 8 Oct 2009 10:49:10 +0200 (CEST)
To: simon@zsi.at
Subject: =?UTF-8?B?U3VydmV5IHJlZ2lzdHJhdGlvbiBjb25maXJtYXRpb24=?=
Date: Thu, 8 Oct 2009 10:49:10 +0200
From: ZSI Survey Admin survey@zsi.at
Message-ID: 712d1b0ffc0cb6b3a11416ebe5eb2dc5@survey60k.zsi.at
X-Priority: 3
X-Mailer: PHPMailer (phpmailer.sourceforge.net) [version 2.0.2]
X-Surveymailer: ZSI Survey Tool:Emailer (LimeSurvey.sourceforge.net)
MIME-Version: 1.0
Content-Type: multipart/alternative;
boundary="b1_712d1b0ffc0cb6b3a11416ebe5eb2dc5"

--b1_712d1b0ffc0cb6b3a11416ebe5eb2dc5
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Dear x,You, or someone using your email address, have registered to participate in an online survey titled test1.To complete this survey, click on the following URL:http://survey60k.zsi.at/index.php?lang=en&sid=48985&token=hmkzn6vnvxhyqqbIf you have any questions about this survey, or if you did not register to participate and believe this email is in error, please contact ZSI Survey Admin at survey@zsi.at.

--b1_712d1b0ffc0cb6b3a11416ebe5eb2dc5
Content-Type: text/html; charset=UTF-8
Content-Transfer-Encoding: 8bit

Dear x,

You, or someone using your email address, have registered to participate in an online survey titled test1.

To complete this survey, click on the following URL:

<a href='http://survey60k.zsi.at/index.php?lang=en&sid=48985&token=hmkzn6vnvxhyqqb'>http://survey60k.zsi.at/index.php?lang=en&amp;sid=48985&amp;token=hmkzn6vnvxhyqqb</a>

If you have any questions about this survey, or if you did not register to participate and believe this email is in error, please contact ZSI Survey Admin at survey@zsi.at.

--b1_712d1b0ffc0cb6b3a11416ebe5eb2dc5--

I also append the mail source as file, since it gets rendered in this BTS.

And of course, the solution is as simple as adding a single space before the linebreak.

I can't reproduce this bug on 1.86. Please upgrade to the latest version.
If the bug persists using the latest stable version please reopen this issue.