SSL & File Attachments

We are using the Upload module to upload documents to our Pages. We are redirecting http URLs to https in httpd.conf to create a secure connection. When we do this, file uploads usually don't work. Does anyone know how to overcome this problem?

Here is a detailed description of what is happening:

On a PC, when I edit a page and go to the "File Attachments" section, I navigate to a file location and choose "Attach." In FF, I get an error message that says "An error occurred: Unspecified error" along with a pop-up saying "Security warning. Although this page is encrypted, the information you have entered is to be sent over an unencrypted connection and could easily be read by a third party. Are you sure you want to continue sending this information?" If I choose to continue, the "File Attachments" section just changes so it shows the "Attach new file" text box again, but doesn't show the moving "status box" which makes it look like the file is uploading. And the file name & location doesn't appear in the "File Attachments" section as it does does when this is working properly. When I "Submit" the page, the file isn't shown as attached to the page and is not uploaded (I checked the files directory).

In IE on a PC, I just get a message saying, "This page contains both secure and nonsecure items. Do you want to display the nonsecure items?" It then acts like it's uploading the file (showing the moving "status box"), but when that's done, it doesn't display the file name as it should. I can then "Submit" the page, but the file isn't shown as attached to the page and is not uploaded.

Another user has gotten similar errors on the Mac, and though the filename is never displayed as it should be after the moving "status box" finishes its action, she has gotten some of her files up there (everything in the files directory she has uploaded). However, this only seems to work some of the time.