Re: MIME's "Content-Disposition" Header

[Terry Crowley <[e-mail]>]

I'm a little confused as to why this issue isn't considered more 
critical within the MIME community.  Successfully transmitting the name 
of an attachment and correctly noting whether some textual information 
is to be treated as an attachment or as part of the message body is 
also very important.  We have some pretty bad failure modes when this 
information is not correctly transmitted.

In particular:

like several other PC-based mail clients, we use a specially-named 
attachment to pass custom rich text, custom attributes and forms 
information.  When this name isn't preserved, the MIME-based Unix 
version can't recognize this information.  (Note that we're trying to 
get this through gateways, so we're not simply talking MIME to MIME 
mailer here and that limits the strategies we can take).

Also, by default the client will send the text body as both plain text 
and within this special attachment (along with the formatting info).  
When our client receives the message, it assumes the text of the 
message is completely specified in the attachment and discards the 
actual body.  If a gateway has inserted the attachment into the body, 
the attachment is completely lost (I won't go into details about why 
this makes sense).  Bottom line is the Content-Disposition becomes a 
pretty important piece of information.

Terry