[imp] IMP with dynamic is surprising users with how far delete goes

[francis picabia]

At our site, we've had dynamic mail with IMP active for roughly 3 weeks.

Today we have our second user to restore from backup after a user
"accidentally" deletes all of their email.  I had difficulty
understanding this until the second occurrence.

In traditional mode, the email is displayed in pages. This is like
many online email services at hotmail, google mail, etc.

Users are accustomed to selecting the upper check box to select
everything on the page (all viewable on the screen).  They select
delete, thinking it is only the messages they see at the time.  In
reality, it selected everything in their mailbox. They purged,
thinking it was only the messages in front of their eyeballs being
purged.  Of course, it deleted and purged everything in their mailbox.

It now appears traditional used pages in a manner more conventional to
what the users expect.

We never had whole mailboxes deleted like this in a long time of using
traditional IMP.

What can be done to reduce the occurrence of accidental email deletion?