On Tue, 29 Nov 1994, Pete Resnick wrote:
> I am trying to subscribe to a list which distributes its digest in MIME
> format. Unfortunately, it looks like somewhere along the line, the 2 MIME
> header lines in the message (Mime-Version and Content-Type) are being
> stripped out ...
> Is there any way to convince LISTSERV to keep these headers around?
 
Hey!  I know the answer to this one!  I actually found out because I was
in the middle of writing a document about mailing list managers, and had
to ask Eric the same question.  Here's the relevant section from my
document:
 
----------------
When mail is forwarded to a list, some headers shouldn't be included -- one
example is the "Return-receipt-to:" header, which if distributed to the list
can result in an overwhelming flood of automated responses to the sender's
system.  There are two main approaches to sanitizing the headers: excluding
known dangerous headers, and passing only known safe headers.  Majordomo uses
the forbidden-headers approach, stripping them in its "resend" routine.
ListProc uses the opposite approach, passing only the headers it knows and
stripping the rest.  Both can have their criteria modified by the system
administrator; such changes are system-wide.  (By the way, ListProc 6.0c has
a problem with MIME no matter how it's configured: it passes only the first
line of a "MIME-Version:" header, thus trashing complex MIME documents.  CREN
ListProc fixes this.)  SmartList lets you choose either approach, on a
list-by-list basis.  LISTSERV also lets you use either approach, but
selecting from four types of header on a user-by-user basis, with the list
owner choosing the list default.  "Short" headers are like ListProc's; "Full"
headers are like Majordomo's; "IETF" headers are the absolutely unmodified
originals, with nothing stripped; and "Dual" headers are for users of rotten
PC MUA's that don't show headers (they result in a "Short" RFC822 header,
followed by a message body repeat of the most important header information).
----------------
 
Now that I look at it, the answer isn't obvious from what I've written --
but the point is that if you set your headers to something besides
"Short" or "Dual," LISTSERV will stop filtering out the MIME stuff. If
you want LISTSERV to keep its hands off them entirely, IETF's the one
to use.
 
Hope this does it for you.
 
Norm