Thunderbird MIME mixup

Today I decided it was time to introduce my iPhone to the campus wireless network, instead of using the slow GPRS network of my carrier. I’m still a happy user of the first generation iPhone, so I’m stuck with GPRS and that’s why I like WIFI.

So I downloaded the already made VU-iphone.mobileconfig file to my workstation and fired up my favorite MUA, what happens to be Mozilla Thunderbird to mail the configuration as a attachment, just like the way the online manual described. But as soon as I opened up the mail app on the phone the message looked like normal text and there was no attachment to open. I decided to use Mutt as an alternative and repeated the steps described above. This time the attachment showed up as it should be. So I was able to import the wireless configuration and finished the wireless setup.

Now I’m happy being wireless connected but still curious why the attachment send by Thunderbird did not show up correctly in the mobile mail app. So I compared both mail clients MIME behaviour and it appears that Thunderbird is not behaving correctly according to rfc2183. As you can see it uses Content-Disposition type ‘inline’ instead of the correct ‘attachment’ type.

I have stripped the irrelevant header and body information of the message.


User-Agent: Thunderbird (X11/20090320) MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="------------070008030904000701030203" This is a multi-part message in MIME format. --------------070008030904000701030203 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit --------------070008030904000701030203 Content-Type: text/xml; name="VU-iphone.mobileconfig" Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="VU-iphone.mobileconfig"


MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="WIyZ46R2i8wDzkSu" Content-Disposition: inline User-Agent: Mutt/1.5.18 (2008-05-17) --WIyZ46R2i8wDzkSu Content-Type: text/plain; charset=us-ascii Content-Disposition: inline --WIyZ46R2i8wDzkSu Content-Type: text/plain; charset=us-ascii Content-Disposition: attachment; filename="VU-iphone.mobileconfig"

This looks like a bug..