More than one DKIM signature in your message with an attachment with a name in Russian. What is the problem?

Question

Microsoft Exchange

Installed the Exchange DKIM Signer agent, constantly DKIM signature error if the attachment is in Russian, if the attachment is in English, numbers or without attachments, then the letters come without errors.
Original post:
Content-Type: application/octet-stream; name= "Servers added to MOM in the last 2 months "
Content-Description: "Servers added to MOM in the last 2 months"
Content-Disposition: attachment; filename= "Servers added to MOM in the last 2 months"; size=9302; creation-date="Fri, 17 Jan 2014 10:26:04 GMT"; modification-date="Tue, 17 Jul 2012 06:32:13 GMT"
Content-Transfer-Encoding: base64

Answer 1

Create a case: https://github.com/Pro/dkim-exchange/issues/151
It will be faster than waiting for an answer here. The developers are very cool guys, they can even compile a version for your extension if they find the time (I hope you don't have it localized?)

Answer 2

DKIM requires that the letter conform to RFC 5322, RFC 5322 does not allow the use of 8-bit characters in message headers. Encode filenames in headers with quoted-printable or base64.

Content-Type: application/vnd.openxmlformats-officedocument.wordprocessingml.document; name="=?UTF-8?B?0KLQtdC60YHRgiDQtNC+0LrQu9Cw0LTQsC5kb2N4?="
Content-Disposition: attachment; filename="=?UTF-8?B?0KLQtdC60YHRgiDQtNC+0LrQu9Cw0LTQsC5kb2N4?="