Multipart messages displayed incorrectly

[Rutger]

Sometimes multipart e-mails are not displayed by Roundcube. I have also tried with Squirrelmail and although Squirrelmail does not recognise the e-mails as rich cq. HTML, it does display the e-mail as plain text (with unparsed HTML tags).

After investigating the differences between working and non-working e-mails, I have found the problem lies within the MIME-Version declaration.

This e-mail works correctly and is displayed as HTML:

From: xx <xx@xx.xx>
To: <xx@xx.xx>
Subject: xx
Date: Thu, 24 Sep 2009 00:08:44 +0200
Importance: Normal
In-Reply-To: <265ba72ae4e831ba565db107f57a637b@localhost>
References: <265ba72ae4e831ba565db107f57a637b@localhost>
MIME-Version: 1.0
X-OriginalArrivalTime: 23 Sep 2009 22:08:44.0755 (UTC) FILETIME=[6AC73230:01CA3C9A]

--_e7c9b96d-7344-4797-aca9-45b93ea779c2_
Content-Type: text/plain; charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable

This e-mail does not work (not displayed at all in Roundcube, displayed as plain text in Squirrelmail):

From: xx <xx@xx.xx>
To: xx <xx@xx.xx>
Subject: xx
Date: Wed, 23 Sep 2009 12:38:22 +0200
Importance: Normal
In-Reply-To: <3241682f02e4f9ff9f7862de571cee96@localhost>
References: <COL108-W24237F958806FC7342FE9E9ADB0@phx.gbl>
X-OriginalArrivalTime: 23 Sep 2009 10:38:22.0951 (UTC) FILETIME=[F9757F70:01CA3C39]


 <3241682f02e4f9ff9f7862de571cee96@localhost>
MIME-Version: 1.0

--_2050211d-3438-4a17-b7ca-db95072ef6f3_
Content-Type: text/plain; charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable

When I add "MIME-Version: 1.0" somewhere between other headers, for example like below, the e-mail is displayed correctly in both Roundcube and Squirrelmail:

References: <COL108-W24237F958806FC7342FE9E9ADB0@phx.gbl>
MIME-Version: 1.0
X-OriginalArrivalTime: 23 Sep 2009 10:38:22.0951 (UTC) FILETIME=[F9757F70:01CA3C39]

I assume the not working headers are conflicting with the standards, but these are produced by Hotmail and therefore are quite common..

[alec]

This is server issue. Roundcube relies on BODYSTRUCTURE reply from IMAP server. In this case the structure is probably bad. Enable imap_debug and check bodystructure in log.