quoting umlauts in header lines

Hi,

I have a autoreply transport in my exim configuration. There I set the
subject line of the reply message. The problem is that this subject
can contain 8bit characters (german umlauts). When using these
directly I get an error from exim. Then I wanted to quote them, but
didn't find the correct way. There are the string expansion operators
escape, from_utf8 and rfc2047, but none of them leads to the correct
result. For example, using rfc2047 transforms the line

Ich bin nicht mehr im Büro

to

=?UTF-8?Q?Ich_bin_nicht_mehr_im_B=FCro?=

So what do I have to use to correctly quote these lines?

Regards
Marco

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Marco Herrn herrn@gmx.net
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