BESX does not require a corporate data plan
If you are connected to the BESX server on campus, you do not need to pay for the corporate data plan through your cellular carrier.
As of April 2011, all BlackBerry users on campus who were previously part of the BlackBerry Enterprise Server (BES) have been migrated to the new BlackBerry Enterprise Server Express (BESX).
The old BES server required that BlackBerry users pay for a corporate data plan through their cellular carriers. This is no longer necessary for users of BESX. If you are currently paying for a corporate data plan because you wanted access to Exchange on your BlackBerry through BES, you can cancel that feature of your cellular contract.
The corporate data plan is typically $10 to $15 more expensive than the standard data plan. You need to keep the standard data plan for your BlackBerry.