[Mimedefang] Exchange sends multipart/alternative instead of multipart/mixed

Kenneth Porter shiva at sewingwitch.com
Fri Dec 1 22:21:53 EST 2006

I've encountered a 3-part message with the following header:

X-MimeOLE: Produced By Microsoft Exchange V6.5.7226.0

The message comprises 3 parts: A "look at this" message (text/plain, 
UTF-8), another message being forwarded (text/html, ISO-2022-jp), and a 
corporate disclaimer (text/plain, no charset specified). The package is 
sent within a multipart/alternative, which says that all 3 parts are 
supposed to be same content with different degrees of richness, best last, 
so Mozilla Thunderbird displays only the disclaimer. It lacks a UI to 
select other alternatives, so it's impossible to see the real meat of the 

First, has anyone else seen this brain damage? Is it due to an Exchange 
misconfiguration? (Ie. can I recommend a specific action to the sender's IT 
department, short of replacing Exchange?)

Second, is it reasonable to fix this in MD by replacing 
multipart/alternative with multipart/mixed in the outermost Content-Type 

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