Xoutpost.com - Central Locking Question

I know there have been numerous posts related to central locking and the alike but I need confirmation that I’m not going crazy. Over the past couple of months the driver door in my 2005 4.4i X5 no longer locks when the door is open and I press the lock button on the fob. The alarm engages but the door does not lock after closing. I can lock the other doors while they are open with no problem. I had it in the dealer for repair but it still does not lock even after both front actuators were replaced. Now the dealer insists that the driver door does not lock when open to prevent locking the key in the car. I swear that it was possible to lock the driver door while open. Your input would be appreciated.