$100 T-Bill from Treasury Direct

Last week, I placed an order for a $100 4-week T-bill as an experiment. The only problem I have had with the site is trying to swap out my local bank for ING Direct. According to the Treasury Department, a notarized change of bank form is not good enough. For some reason, they want a bank official to witness my signature. At this point, I am waiting for them to respond to my inquiry on how to make that happen.