OK man, I got you covered. You can downlaod and install the latest sprint ROM to update the radio. Dont let the customization take place after flash (if there is any) then go here
Code
http://www.htcforums.com/touch-cdma-vogue-p3050-xv6900-f10/cellular-touch-new-rom-gps-t1197.html
And follow the instructions. It should all be working then. After that, flashing a custom rom should be a snap.