[Email-SIG] why is this HeaderParseError being raised?

[Jason R. Mastaler]

Tokio Kikuchi <tkikuchi at is.kochi-u.ac.jp> writes:

>> I'm probably missing something obvious, but can someone tell me why
>> email.header.decode_header() is blowing up when trying to decode the
>> Subject header of this message?  It looks legitimate to me.  It's not
>> a spam message, and was prodcued by Microsoft Outlook Express:
>> 
>> http://mastaler.com/tmp/1150650768.21756.msg.txt
>
> You need two trailing paddings (=) in the encoded string.
>
> Subject: 
> =?iso-8859-1?B?UmU6IEFXOiBCZXN0ZWxsdW5nIEJhZ3RhZ3MgZvxyIEdvbGYgQ2x1YiBL/HNzbmFjaA?=
> should be
> Subject: 
> =?iso-8859-1?B?UmU6IEFXOiBCZXN0ZWxsdW5nIEJhZ3RhZ3MgZvxyIEdvbGYgQ2x1YiBL/HNzbmFjaA==?=
>
> In RFC3548,
> Implementations MUST include appropriate pad characters at the end of
> encoded data ...

Thanks.  Any idea what might be causing this?  I haven't heard of
Outlook Express being RFC 3548 non-compliant before.