I can't save the attachments from an S/MIME Opaque signed message. I can see them in the message window but when click on them nothing happens.  When I click on the "Save Attachments" I got a dialog which says: "Found no attachments to save"

When  hovering over the attachemt I see in the status bar something like this: "attachment:2:2?place=body".

If I use "normal" S/MIME, everything works fine but other MUA-s (Thunderbird) prefers the Opaque way. I have to use a Thunderbird to read those e-mails, it's very frustrating.

Reproducible: Always

Steps to Reproduce:
1. Acquire and setup an S/MIME cert and key.
2. Write a new message, attach a file to it. Enable signing, set Cryptographic Message Format to S/MIME Opaque.
3. Send the message.
4. Open the received message and try to open/save the attachment.
Actual Results:  
You can't open/save the attachment.

Expected Results:  
You can open/save the attachment.