On the blackberry open up the inbox options - Email reconciliation and ensure that Wireless reconcile is set to "on". If that doesn't work try to delete and undelete the "Desktop [CMIME]" service book and if that doesn't work make a backup (without service books), wipe the device, restore and do an enterprise activation. This will pull down a fresh set of service books and should resolve the issue for you.
Everyone has a photographic memory. Some just don't have film. (Steven Wright)