mail back to UTF-8 before save to HD

[Emanuel Berg]

(case 1) If I write a mail with the Swedish chars "å",
"ä", or "ö", as in

    äåö
    ÅÅÖ

the mail gets the headers:

    Content-Type: text/plain; charset=utf-8
    Content-Transfer-Encoding: quoted-printable

(case 2) But if I don't use any of them chars, there
is only:

    Content-Type: text/plain

However when the mail from (case 1) is archived in my
nnml group mail.sent, the UTF-8 isn't restored but the
"quoted-printable" style remains:

    =C3=A4=C3=A5=C3=B6
    =C3=84=C3=85=C3=96

I wrote this zsh to restore it:

    back-to-swedish () {
        local files=($@)
        sed -e 's/=C3=A5/å/g; s/=C3=A4/ä/g; s/=C3=B6/ö/g' \
            -e 's/=C3=85/Å/g; s/=C3=84/Å/g; s/=C3=96/Ö/g' \
            -e 's/=20/ /g' $files
    }

(I don't know why the whitespace at the end of the
signature delimiter must be restored as well. It gets
sent and archived as =20.)

My question is, how can I automatize this so the UTF-8
is restored automatically if it was used in the
original message?

-- 
underground experts united
http://user.it.uu.se/~embe8573