[Users] About the base64 problem with Yahoo

Paul claws at thewildbeast.co.uk
Fri Oct 18 13:12:03 CEST 2013

Hi Steve,

Thanks for sending an example off-list.

On Wed, 16 Oct 2013 22:06:28 -0400
Steve Litt <slitt at troubleshooters.com> wrote: 

> Here's my question:
> * What do the RFCs say about the necessity of a mail client
> decoding a text/plain; charset=utf-8 that's encoded base64. I'd
> love to be able to tell them "sorry, the RFC's say that's a no-no,
> the bug is with Yahoo for base64ing the text part of the message".
> If the RFCs say an email client *should* convert the base64 in the
> plain text part of an email, be aware that this is going to happen
> more and more as more and more people are in Yahoo Groups. Yahoo
> has little incentive to change, because most other clients either
> convert, or show the HTML by default, or both.

The problem with yahoo's messages is this:

They should use this: "Content-Transfer-Encoding: base64"
But instead are using this: "Content-Transfer-Encoding: base64 "

Note the extra space at the end.

The html part displays fine because on that part there is no extra
space. That is, on the html part they don't make the same mistake.

According to the RFC, this extra space at the end is not allowed.
See http://tools.ietf.org/html/rfc2045#section-6

I will add a workaround to Claws so that it ignores this space, but,
(my opinion of the RFC is that), it is yahoo who are at fault and not

with regards


It isn't worth a nickel to two guys like you or me, 
but to a collector it is worth a fortune 

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