Are you referring to when the device is plugged in the charger, the screen becomes a clock? If so it's on the newer OS's...
that i don't know and since i can not provide you with a link because i am new here i have to post 10 times before i could but if you go to the main BB site you'll see what i'm talking about
You can't, it's for newer Operating Systems, the software you're running on your device does not have it. The Bold, Storm and Tour have this feature...