Mail 4.5 (1084) is not automatically downloading larger attachments.

Question

Mail 4.5 (1084) is not automatically downloading larger attachments (i.e. a 2 MB file) without the user clicking on the SAVE button or the attachment icon (white square with down arrow).
Before download:
The problem is that if the user accidentally deletes the message before downloading the attachment, and then views that message in the trash OR moves the message from the trash back to inbox, the attachment is lost and message appears garbled up.
This is not a problem if user clicks SAVE or clicks attachment icon itself before deleting it - message and attachment will be readable in trash and when restored to inbox.
Question:
Is there a way to force Mail to download all attachment regardless of size without requiring user interaction?
Thank you
ig

Answer 1

Actually smaller attachments are downloaded automatically, or perhaps it depends on attachment type? 
Try the same with say 2MB .PPT file .. email the file to yourself. It will come through as "click to download" icon (see image above). Trash the message (before SAVE or clicking on attachment), now try opening it in the trash or pulling it back to inbox and then open it. Attachment is gone and you get garbage - clearly extra data is there but is non-readable.
Not a big issue for a single user - potentially very big issue for an admin supporting large number of end-users, some of which are recent Outlook transplants.
Btw, I'm using IMAP server and I have enabled "Store deleted messages on the server"