attachment name in UTF-8 sent incorrectly

Dear Sir/Madam,

I have a problem with attachment names in SD+ 8.0 8016
When I am trying to make a reply from request and attach a file with non-ascii characters in name it is being displayed incorrectly with Lotus Notes 8.5.2

I have found out the the problem is in the way that SD+ uses to name attachment while sending.
The exapmle of SMTP code with WRONG name:

Content-Type: multipart/mixed;
        boundary="----=_Part_881_27909834.1319713300571"

------=_Part_881_27909834.1319713300571
Content-Transfer-Encoding: quoted-printable
Content-Type: text/html;charset="UTF-8"

<style>p { margin-top:0px; margin-bottom:0px}</style>=D0=BF=D1=80=D0=BE=D0=
=B2=D0=B5=D1=80=D0=BA=D0=B0<br /><br />
------=_Part_881_27909834.1319713300571
Content-Type: application/octet-stream;
        name="=?utf8?B?0YDRg9GB0YHQutC40Lkg0YTQsNC50LsuZG9j?="
Content-Disposition: attachment;
        filename="=?utf8?B?0YDRg9GB0YHQutC40Lkg0YTQsNC50LsuZG9j?="
Content-Transfer-Encoding: base64

If I change the content (change utf8 to utf-8) and send the same data via SMTP the attachment name comes OK:

Content-Type: multipart/mixed;
        boundary="----=_Part_881_27909834.1319713300571"

------=_Part_881_27909834.1319713300571
Content-Transfer-Encoding: quoted-printable
Content-Type: text/html;charset="UTF-8"

<style>p { margin-top:0px; margin-bottom:0px}</style>=D0=BF=D1=80=D0=BE=D0=
=B2=D0=B5=D1=80=D0=BA=D0=B0<br /><br />
------=_Part_881_27909834.1319713300571
Content-Type: application/octet-stream;
        name="=?utf-8?B?0YDRg9GB0YHQutC40Lkg0YTQsNC50LsuZG9j?="
Content-Disposition: attachment;
        filename="=?utf-8?B?0YDRg9GB0YHQutC40Lkg0YTQsNC50LsuZG9j?="
Content-Transfer-Encoding: base64

Is it possible to change this in configuration?

Gennady