I have an unlocked 6315 in which I used my AT&T sim card. I migrated to Cingular and their sim card will not work. Cingular response is they do not support the phone and maybe I need a firmware upgrade. Is anyone out there using a 6315 on the Cingular network or has any suggestions.
Cingular uses 2 type of 64k sim cards. They are made by two different companies. One has black writing ann one has gold writing on it. One of them the IPAQ won't detect. So just goto any Cingular store and have them switch yours. (It's free, or at least is was for me).... if you can't find the 64k sim other than yours, then just ask for an old 32k sim. It will work fine.