Im in the market for a wifi smart phone with maps and am looking into unlocked Nokia phones. The Lumia 800 and 900 jump out to me as possible selections, or maybe even an old e71 or e72. If I purchased an unlocked model of the 800 or 900 would At&t automatically detect that I am using a smart phone? I've read that At&t detects smart phone use of models they sell, and I wouldn't want them to slap me with a data plan when using one of these phones. Would I be better off with purchasing an e71/e72 or another type of Nokia phone? FYI I'm using an old blackberry pearl (Rodgers) and havent been hit with a data plan and its been nearly four years I've been using the Blackberry.