HELP! Am I boned? I updated my ROM -> WM6 before activating

[sshrum]

I upgraded my new replacement phone rom with the WM6 (working great on my old PPC-6700)...now when I called Sprint to activate the new phone, it isn't excepting the ##544088# code...it just sits there.

I tried to downgrade the firmware back to the version on Sprints site but the installer is not completing indicating that it is having problems getting the version information off the phone.

Sprint advanced tech support indicates that this goes beyond their level of customer support (took me 2 hours to hear that...was sorta what I was expecting).

Anyone have a workaround or know how to temporarily downgrade the ROM to the sprint factory release?

TIA