Sweetkitty:
You seem to be confusing the constitutional mandated separation of Church and State with private and corporate rights.
Mattel has every right to produce a Christian Barbie if it so chooses, and there ain't a darn thing any of us, or the Government, or the Church, or my dog, could do about it; save protest with our paychecks. Mattel could produce a Wiccan, or a Buddhist, or an Islamic, or even a Satanist Barbie if they wanted to. That is their right.
Mattel, or any big business for that matter, makes what sells...period. If a "Wiccan" Barbie sells and a Christian Barbie wouldn't, maybe you should be spending less time in "righteous indignation" and more time figuring out why you have so little influence on people?