We have a need to customize the existing Zen cart file upload attribute.

Rather than simply uploading any file to my server , i would like the file type to be restricted to image files only.

Once uploaded, I would like the users to be able to see a thumbnail preview of their image in the cart checkout page. The file will then be sent to an email address (same every time). I don't necessarily want the file stored on the webspace. This will need to be plugged into the existing cart.

Thanks for your time.