Originally Posted by Branko
It uses both data and sms, but mostly uses data to communicate with the other end of the im client.
I'd say a more direct answer to her question would be that each message sent and received takes up a message from the person's SMS messages pool. This is due to the way the client was designed by Oz (not sure if the SMS was a request of TMO). Now, when the 7100t was first released, you could go to your SMS options and change it to send the SMS messages over the GPRS data network instead of the GSM voice network, thus bypassing the SMS messages pool issue altogether.
Now, back to my question that wasn't answered, why was the SMS over GPRS feature disabled by T-Mobile? Was there a technical reason behind it, or was it simply the fact that it is a new feature of some phones that was not previously encountered, and when the boom of sales for the 7100t happened and more and more people started skirting past their SMS fees by enabling the feature, it was disabled by TMO on the network side, thus being more of a Billing reason (read: greed) rather than a Technical reason.
P.S. - Most people who post on here from the carriers or directly from RIM tend to conceal their identities, most commonly because of questions such as mine above - or the nature of announcing your identity tends to lead to question after question after question, and most commonly being questions that have already been answered multiple times. My guess is that you are possibly new to T-Mobile or to the wireless data group, or just have recently taken an interest in BlackBerry services (just a guess), thus the enthusiastic announcement of employment. Anyhow, it may have been easier on you had you just helped anonymously, because the day you decide that people on here ask too many questions, or they tend to lean on your online presence rather than calling TMO's support line, then their blame will point directly back to you. $10 says that if you search your database there within the next few weeks, you'll find some reference to Branko on BlackBerryForums.com. I just hope, for your sake, that Branko has no direct reference to your real name.