Switching from Sprint to Alltel

[cmg0788]

I bought a ppc-6800 on ebay that appears to be from sprint, except for the fact that it's loaded with the Alltel ROM. How exactly can I set it up on my Alltel service with my own Alltel phone number programmed in? I called in and Alltel refused to activate it.

I know I need the MSL from sprint, and I need to put it in using ##778# but what do I do after that to make sure that I can use the phone on my Alltel phone number? Can anyone give me a step-by-step?

Any help is appreciated