Not quite sure how it works with AT&T but with t-moible, you need the data plan (BIS or BES). As far as I know, only OZ messaging compatible phones (ie. the 8100 pearl) uses text messages for IMs.
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He who knows, and knows not what he knows, knows nothing.
If you have the BB data plan, go to www.blackberry.com/instantmessaging on your BB browser and from there you can download whatever IM programs are available for your carrier and device. The IM programs from there use data.
I know for Verizon, if you use their MobileIM application each incoming/outgoing message is counted as one outside-of-Verizon text. My messaging plan, however is only 1500 outside of Verizon, so I was wondering if there were any apps that would not have messages count as texts.
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