well on AT&T, i have 2 sims (both blackberry enabled, and i use BES for both). but, one sim is BBC and one sim is "normal" blackberry. what i mean is, i cannot access BBC with the "normal" blackberry sim. i'm not sure if i am saying this correctly, but with AT&T, you need the specific BBC plan in order to use blackberry, not a "normal" blackberry enabled sim that you would use with a blackberry device.