When trying to open or download a ZIP attachment (test emails created with Thunderbird 2 and RC), it's handled in the wrong manner by the browser (tested with Firefox 2 and IE 7):
Clicking the attachments link:
The current windows is cleared and all the binary garbage is displayed right away.
Right-click and "Save as...":
The proposed file type is "HTML file".
This all sounds like a completely wrong MIME type is being sent in the HTTP header when sending the attachment data.
Versions:
RC: SVN 462
Apache: 2.0.0.59
OS (server): Win2kServer
OS Client: XP Pro SP2
PHP: 4.4.*
Manfred