Chinese filename in the attachment

[haomiao]

Hi
       I am using gnus to send an receive mail.
       But when my mail has attachment whose filename contains Chinese
characters, other persons who are using outlook or foxmail can not see
the attachment. (gnus can)
       The only thing I can do now is rar the attachment files to
xx.rar which name is all english, then send this rar attachment.
       I have done some test and find that the 'filename' attribute is
different, but I don't know what is the exact explanation and how to
resolve this problem?

       Here is some infomation

       1. mail head from gnus(has Chinese filename)

--=-=-=
Content-Type: application/octet-stream
Content-Disposition: attachment;
 filename*0*=gb2312''%b1%ea%d7%bcPOSP%c5%fa%bd%e1%b8%c4%bd%f8%b7%bd
%b0%b8.;
 filename*1*=doc
Content-Transfer-Encoding: base64
Content-Description: doc

       2. mail head from gnus(has English filename)
--=-=-=
Content-Type: application/octet-stream
Content-Disposition: attachment; filename=F32.rar
Content-Transfer-Encoding: base64
Content-Description: doc

       3. mail head from other mail client(foxmail)  (has Chinese
filename)
--=====001_Dragon584378265126_=====
Content-Type: application/octet-stream;
        name="=?gb2312?B?YnVnemlsbGE2OF/Jz7qjuPbQ1LuvUE9TUM7EvP6x5Lj8x
+W1pV9DSFREODVfMjAwNzA4MDgueGxz?="
Content-Transfer-Encoding: base64
Content-Disposition: attachment;
        filename="=?gb2312?B?YnVnemlsbGE2OF/Jz7qjuPbQ1LuvUE9TUM7EvP6x5Lj8x
+W1pV9DSFREODVfMjAwNzA4MDgueGxz?="