Devs,

I sent a message to myself using RoundCube last week with a couple picture attachments (trying to reproduce ticket #1485342). I couldn't display the attachments, so I thought I had reproduced the problem from the ticket. However, it turned out to be a problem with the e-mail headers on the message sent out by RoundCube (which seems different than what the ticket was describing). Before I dig too deeply into the MIME encoding, I wanted to see if any of you could see any reason why the headers would have been encoded this way.

Here is a section of the headers:

User-Agent: RoundCube Webmail/0.1
Content-Type: =?UTF-8?Q?multipart/mixed;=0A=09boundary="=_02a240d2fbd71132d40be9b4c55e5587"?=

--=_02a240d2fbd71132d40be9b4c55e5587
Content-Type: multipart/alternative;
	boundary="=_3138421b4fcb76298f28ab6e143b4ab2"

--=_3138421b4fcb76298f28ab6e143b4ab2
Content-Transfer-Encoding: 8bit
Content-Type: text/plain; charset="UTF-8"

Notice the invalid Content-Type value. I though it only needed to do the quoted-printable encoding if there were non-7-bit-ASCII characters in the header value (which doesn't seem to be the case here).

Any ideas?