Ok... have an 8700C that I need to upgrade the firmware on. It's an original 8700C via Cingular that I got unlocked and am using it on TMO. Running 4.2.1.66 on it now.

Question: Where would I go for the firmware update? TMO or Cingular? Since it's a branded Cingular phone yet unlocked do they have to provide the updated firmware or can i use the 8700G update on TMO?

Looked on TMO's site and for the 8700G they have 4.1.0.346?

I'm confused....

You can use any firmware on the 8700. RIM writes it all; the carriers test and release it. Looks like T-Mobile never released 4.2 for the 8700. Lots and lots of issues with 4.2 on the 8700...

You can use an unlocked 8700 on T-Mobile.

Wirelessly posted (BlackBerry 8700g: BlackBerry8700/4.2.1 Profile/MIDP-2.0 Configuration/CLDC-1.1 VendorID/100)

You can actually find the latest version of the 4.2 OS as a sticky at the top of the 8700 forum. I am running it (4.2.1.101) right now.