I've read all sorts of different sites how to delete a message permanently off of the Blackberry using Outlook (Exchange), but I need to do the same thing the opposite way.

We have users that often travel for extended periods of time and have no other access to their email to manage the size of their mailbox. For these users, deleting mail from the Blackberry only moves the message to their Deleted Items folder in Outlook then having no real effect on the size of their mailbox overall.

How can I (or can I even) setup a device and Outlook mailbox (or Exchange) so that a deleted message from the Blackberry permanently deletes from their Outlook account too?