Version:           unspecified (using Devel) 
OS:                Linux

When Akonadi is configured to use sendmail for sending mail, it appears to pipe the message to the specified command with \r\n (carriage return, line feed) line endings.  This is incorrect - in this mode sendmail expects native Unix line endings, i.e. \n (linefeed) alone.

I cannot find a definitive source for the line ending requirement, and it is possible that traditional sendmail does not care.  However, if the mail sender agent is actually Debian SSMTP, it does care about the line endings and unconditionally adds another \r (carriage return) to the transmitted message.  Depending on the receiver, this can cause incorrect header or MIME boundary detection.


Reproducible: Always

Steps to Reproduce:
Install SSMTP (ftp://ftp.debian.org/debian/pool/main/s/ssmtp)
Configure the sending mail account to use /usr/lib/sendmail (a link to /usr/sbin/ssmtp)
Send an email with attachments to a Google Mail account.
Observe that the attachments are not recognised correctly, and the message body as displayed by gmail is something like:

-- start -----------------------------------------------------------------
Content-Transfer-Encoding: 7Bit

Content-Type: text/plain; charset="us-ascii"





Message text



--

Signature

Content-Disposition: attachment; filename="xyzzy.gif"

Content-Transfer-Encoding: base64

Content-Type: image/gif; name="xyzzy.gif"



R0lGODlhcQBxAPQfAP//AP/MAMz/AMzMzMzMAMyZAMxmAJnMAJmZAJlmAGaZAGZmZmZmAGYzADNm
(remainder snipped)
-- end -----------------------------------------------------------------



Actual Results:  
Mail is received with additional line breaks, which cause the headers and MIME boundaries to be not interpreted correctly.


Expected Results:  
Mail should be received correctly.


The mail sending works correctly if SMTP is chosen for the mail sending agent.

Trace of write on pipe between akonadi_maildispatcher_agent and SSMTP - \r\n line endings:

[pid 25360] write(13, "From: Jonathan Marten <jjm@keelh"..., 10956) = 10956
 | 00000  46 72 6f 6d 3a 20 4a 6f  6e 61 74 68 61 6e 20 4d  From: Jo nathan M |
 | 00010  61 72 74 65 6e 20 3c 6a  6a 6d 40 6b 65 65 6c 68  arten <j jm@keelh |
 | 00020  61 75 6c 2e 6d 65 2e 75  6b 3e 0d 0a 54 6f 3a 20  aul.me.u k>..To:  |
 | 00030  6d 61 72 74 65 6e 6a 6a  40 67 6d 61 69 6c 2e 63  martenjj @gmail.c |
 | 00040  6f 6d 0d 0a 53 75 62 6a  65 63 74 3a 20 54 65 73  om..Subj ect: Tes |
 | 00050  74 20 33 20 77 69 74 68  20 61 74 74 61 63 68 6d  t 3 with  attachm |
 | 00060  65 6e 74 0d 0a 44 61 74  65 3a 20 54 68 75 2c 20  ent..Dat e: Thu,  |
 | 00070  30 36 20 4f 63 74 20 32  30 31 31 20 31 35 3a 34  06 Oct 2 011 15:4 |
 | 00080  39 3a 33 39 20 2b 30 31  30 30 0d 0a 4d 65 73 73  9:39 +01 00..Mess |
 | 00090  61 67 65 2d 49 44 3a 20  3c 31 33 33 38 35 36 39  age-ID:  <1338569 |
 | 000a0  2e 67 6b 71 33 5a 55 38  57 6e 33 40 6b 65 65 6c  .gkq3ZU8 Wn3@keel |
 | 000b0  68 61 75 6c 3e 0d 0a 4f  72 67 61 6e 69 7a 61 74  haul>..O rganizat |

Capture of traffic between SSMTP and ISP mail server - line endings expended to \r\r\n:

0040  40 b9 46 72 6f 6d 3a 20  4a 6f 6e 61 74 68 61 6e   @.From:  Jonathan
0050  20 4d 61 72 74 65 6e 20  3c 6a 6a 6d 40 6b 65 65    Marten  <jjm@kee
0060  6c 68 61 75 6c 2e 6d 65  2e 75 6b 3e 0d 0d 0a 54   lhaul.me .uk>...T
0070  6f 3a 20 6d 61 72 74 65  6e 6a 6a 40 67 6d 61 69   o: marte njj@gmai
0080  6c 2e 63 6f 6d 0d 0d 0a  53 75 62 6a 65 63 74 3a   l.com... Subject:
0090  20 54 65 73 74 20 34 20  77 69 74 68 20 61 74 74    Test 4  with att
00a0  61 63 68 6d 65 6e 74 0d  0d 0a 44 61 74 65 3a 20   achment. ..Date: 
00b0  54 68 75 2c 20 30 36 20  4f 63 74 20 32 30 31 31   Thu, 06  Oct 2011
00c0  20 31 36 3a 31 30 3a 35  32 20 2b 30 31 30 30 0d    16:10:5 2 +0100.
00d0  0d 0a 4d 65 73 73 61 67  65 2d 49 44 3a 20 3c 31   ..Messag e-ID: <1
00e0  34 37 31 30 36 33 2e 53  4c 65 4d 4e 49 30 66 62   471063.S LeMNI0fb
00f0  63 40 6b 65 65 6c 68 61  75 6c 3e 0d 0d 0a 4f 72   c@keelha ul>...Or