Thank you SWGUY and DBLTOE. I've given myself a little credit, but you all are really helping me feel better.

I started by digging into includes/modules/payment/authorizenet_aim.php where I found a call to the class cc_validate. So I found that class of course in classes/cc_validation.php. From there I realized it was checking what appeared to be constants defined in the database. That's when I realized this problem was likely my doing, or not doing as it were. lol.

Thanks again guys. ;)

Best,
John