From: Ian Bell (ianbell@turnpike.com)
Date: Fri Mar 15 2002 - 09:13:13 CST
On Thu, 14 Mar 2002, Charles Lindsey <chl@clw.cs.man.ac.uk> wrote:
>In Section 4, regarding parameter (both ours, and any we inherit from
>MIME)
>
>[Bruce Lilly
>What about RFC 2231 chars used in attributes, esp. with continuation
>and charsets: "*", "'", "%"]
>
>Well does any Mail system actually implement RFC 2231?
Turnpike does.
We presumably are not alone as the precursor RFC2183 had some issues
which were raised very quickly by other developers who were trying to
implement it. (That was almost five years ago.)
Turnpike will only use it to send MIME parts which include filenames
containing 8bit characters. There is no other way of sending such
filenames until 8bit headers are allowed in mail.
>My feeling is that we just don't want to know
Why? If USEFOR wants to adopt MIME, and it should, then do so warts and
all.
So, if you want to use RFC2045-49, you are restricted to only sending
us-ascii characters in MIME parameters: if you want to send 8bit
characters in MIME parameters, then use the MIME extensions that exist.
> Similar considerations apply to non-ASCII characters within the
> values of parameters (which, according to the syntax, MUST be in the
> form of quoted-strings in order for UTF8-xtra-chars to be
> accomodated). There is NO requirement to support the extensions set
> out in [RFC 2231] for specifying continuations, character sets or
> languages in such values, though reading agents MAY support them.
>
>Is that OK?
No, MIME is not USEFOR's to change. 8bit characters in MIME headers
should not be allowed until MIME is extended to allow it.
So clients MAY implement RFC2231, but if they want to send 8bit
characters in MIME parameters with the Content-Type or
Content-Disposition headers, they MUST use it.
-- Ian Bell T U R N P I K E