[Zope] ExtFile Product and mime-types

After importing a new file via PythonScript manage_addProduct['ExtFile'].manage_addExtFile(id, title, descr, file) some files have automatically the Content-Type 'application/octet-stream'. How do I change the identification of these files afterwards, and how can I change the Product's autodetection for the next files to upload? I use ExtFile Version 1.1.3. -- Best Regards, Marc Roland AICAT CA Technologies GmbH Dipl.-Ing.(FH) System Consultant Friedrich-Karl-Str. 101-103 Fon:+49/(0)221/971445-0 Fax:-5 Germany-50735 Koeln (Niehl)