While performing the RAM upgrade last night, I noticed in the battery area there was an icon for a sim card in the tray right below a little slot for a sim card. The slot appeared to have some kind of foam or other soft substance lodged inside. Would I be correct in assuming that in my model (AOA150-1570) there's no actual hardware in that foamed up port, or is it possible that I could remove that foam and insert my AT&T 3G sim card? Thanks much!