If it makes you feel any better, Bill, just keep in mind that Kodak offers UPS air services for delivery of raw stock (my last couple of orders have been shipped UPS 2nd day air), so I'd say that if Kodak deems UPS air service safe for delivery of their raw stock, then you should be ok. I doubt Kodak film shipments get any preferential treatment once they're picked up and in transit, so putting some type of "DO NOT X-RAY" indication on the box, just as Kodak applies the sticker, should be sufficient.
FYI, Kodak has posted a .pdf of their x-ray label which is available for anyone to download and print. You can download it here.
Incidentally, tomorrow I'm sending off some S16 for processing and transfer which passed through airport carry-on x-ray twice...once on the way out, and once on the way back home. Judging from the information I gathered from a few other threads prior to my trip, I should be ok, as apparently the carry-on x-rays aren't as powerful as the carry-on x-ray machines, but the "what if" is still in the back of my mind
On a related note, does anyone know if FedEx and UPS x-ray their air cargo? I'd imagine that USPS deliveries might be a little more susceptible to x-ray since USPS uses passenger airlines to transport some of their mail, but since FedEx and UPS have their own fleet of cargo planes, I'd be interested to know if they do x-ray their air cargo.