Problems with Speed Download 4 and Safari when downloading RAR files

For a few weeks I now had the problem with Speed Download 4 and Safari when I wanted to download RAR files. I tried everything, uninstalling and reinstalling, disabling all other plugins (SafariStand, Glims, SafariAdBlock) but nothing helped, Safari always used its own download manager instead of handing the download to Speed Download 4.

Then I started to take a closer look at MIME types. Per default, the MIME type(s) setting for RAR archive in Speed Download 4 on my machine was application/x-rar-compressed, application/octet-stream. But I found a list with some more possible MIME types for RAR files. It finally worked again fine after completing the MIME type(s) setting for RAR archive in Speed Download to application/x-rar-compressed, application/octet-stream, application/rar, application/x-compressed, application/x-rar, compressed/rar. Now RAR file downloads are again intercepted by Speed Download 4.