* Additional remarks:

There might be more problems. E.g. `sieve-manage-putscript' contains the
following comment:

    ;; Here we assume that the coding-system will
    ;; replace each char with a single byte.
    ;; This is always the case if `content' is
    ;; a unibyte string.

which seems to indicate that it might also have an issue with multibyte
content (even though I have not experienced any uploading issues). I
will try do some more testing to check that.


In general, it is also not clear to me why the response (or process)
buffer needs to be multibyte enabled at all as it should only be used
for the line/byte oriented protocol data. But the commit message of
8e16fb987df9b which introduced the multibyte handling states:

    commit 8e16fb987df9b80b8328e9dbf80351a5f9d85bbb
    Author: Albert Krewinkel <krewinkel@moltkeplatz.de>
    Date:   2013-06-11 07:32:25 +0000
    ...
        * Enable Multibyte for SieveManage buffers: The parser won't properly
          handle umlauts and line endings unless multibyte is turned on in the
          process buffer.
    ...

so this was obviously done on purpose. I contacted Albert about this but
he couldn't remember the details (it's been nearly 10 years).



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