Hi- I have a T-Mobile branded Nokia 6101b (RM77) that I successfully unlocked with the help of this website. I use this phone with an AT&T Wireless SIM card (Cingular Blue). About a month ago, I needed a new AT&T SIM card which I purchased from ebay. The SIM was brand-new, and has "GemPlus" printed on the back. I had Cingular transfer my account to the new SIM. All appeared to be well except the phone now displays "AT&T Wireless" about 50% of the time. The other 50% it will display "Cingular". When it displays Cingular, I cannot access my voicemail. It just plays a recording that states I should "enter my 10-digit wireless number once my greeting starts". Well, my greeting never starts! When "AT&T Wireless" is displayed, I have no problem getting my messages. I've installed the new SIM in two other unlocked phones with no problems accessing voicemail. The phones are: Motorola V180 (AT&T Wireless), Samsung X-495 (T-Mobile). These two phones never display "AT&T Wireless", just "Cingular". I phoned Cingular Tech Support, and they tried an Over the Air (OTA) software upgrade which they said was unsuccessful. The voice mailbox number is my 10-digit wireless number in all three phones. Cingular Tech Support also stated that my voice mailbox number was wrong. They gave me a number starting with a 207 area code. I can't seem to be able to change the voice mailbox number on the phone- the menu is grayed out and displays "Not allowed" when I try to access it. I don't know why I would need a different voice mailbox number JUST for the Nokia 6101b.
Is there a fix for this? Thanks in advance for any help, and sorry for the long post!

Arthrodesis