Re: Problems with 8-bit headers

[Florian Weimer <fw@deneb.cygnus.argh.org>]

Vladimir Volovich <vvv@vvv.vsu.ru> writes:

> * possibility to auto-select the charset for 8-bit chars in headers
>   depending on the charset used for the message body

Yes, I agree that's a nice feature. ;)

> * possibility to set up preferred charsets to encode message bodies on
>   a per-group basis.

> * possibility to specify that the preferred charset to encode a
>   message body should be the same as the charset used to encode the
>   message (or mime part) i'm replying to.

Currently, these two features are very hard to implement, at least
in the general case, because Emacs unifies only ASCII characters in
different MULE charsets.  For example, an ISO-8859-1 "ä" and one in
ISO-8859-2 are completely different characters from Emacs' view.  As a
result, it is impossible to decide whether the preferred MIME charset
can be used---without additional mapping tables.  On the other hand,
such tables do exist for almost all charsets used on the world. They
are known as Unicode. ;)

IMHO, these features have to wait until Emacs switches to Unicode for
internal character representation.