I don't think they let you, since it is an AT&T branded phone. If you pop your sim card in there, they automatically upgrade your plan. They must have changed that when they changed the plans, since I used a Blackberry for 6 months without data, but when I gave it to my girlfriend to use, it automatically added the data. I think it doesn't happen with the N1 because it wasn't carrier branded (they might have a list of IMEIs or something). You could try the Asian or Australian version, but I'm not sure if that would trick them.
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