Yea, for some carriers MMS/SMS (and a bunch of other things) are controled by the Service Books.
On your BlackBerry Options -> Advanced Options -> Service Books.
Best thing to do is just re-send the service books, either from the BIS website or from the email setup icon.
8830 -> 8330 -> 9550 -> 9650
Just think about how far BlackBerries have come from then till now... And what else is coming.
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