Had the same basic experience with a young woman at U.S. Customs in Miami in 1996, when returning from a bird hunt in Argentina. I handed her the 4457's for my pair of shotguns, and she said they were no good, since you had to get a new one filled out every time you left the country. I said no, you don't, but she insisted, so I said, "Get your supervisor." He took one look at the forms and waved me through.
