imap.GetMailAttachFilename returns filename ?=

Hello,

I recieve bad attachment filenames with the imap.GetMailAttachFilename method in VB6 when the attached filenames contain german Umlaut (äöü etc.)

example:

Dim numAttach As Long, nameAttach As String 
Dim filetype As String, Filename As String 
nameAttach = "" 
numAttach = imap.GetMailNumAttach(email)
If numAttach > 0 Then
    For J = 0 To numAttach - 1
        Filename = imap.GetMailAttachFilename(email, J)
        ...

the variable Filename contains ?=DCbungsseite.docx?=

Is this a known problem? How can I solve it?

Best regards, J.S.