iPhone identification by carrier (AT&T)

So we have activated using iNdependence a couple of iphones with sims from at&t. The motivation is not to sign another 2 year contract here ... but we observed the following (this is for folks with at&t accounts currently).

The carrier identifies the device as an iPhone and shows so in the account access pages (web). It also does something else just based on that information which is drop any discounts your account may have [ like corporate discounts, group discounts, etc]

So this begs the question: where is the identification of the phone obtained ? Is this part of the GSM protocol someplace ? Or is this part of some request the phone submits on EDGE ? Can we masquarade this request not to reveal the device's true identity or this impossible ?

Most probably by IMEI. Not much you can do, I guess - I do not know of any app to change your IMEI, not to mention that it might be illegal to do so (it is in some EU countries)

Wowww....I was just trying to find out the same thing, and so far unless someone else knows different...I think it's based off of the IMEI as stated.

I'm tryin to find out because my SIM card in my blackberry doesn't get charged for data...but when put into ANY other device, it does.