It wasn't hairspray, it wasn't Velcro and it wasn't gravity. It was toupee tape that held up Jennifer Lopez's memorable Grammy dress. "It wasn't going to move," the actress-singer told TV's "Entertainment Tonight" in an interview to be broadcast tonight. Toupee tape, a staple in Hollywood makeup departments, is two-sided and clear, and considered extra sensitive. (It also adheres to fake beards and mustaches.) "It didn't seem that out there to me," Lopez said of the barely-there ensemble that was designed by Donatella Versace and which is still causing talk since Lopez wore it to the Grammys two weeks ago. "It was a good-looking dress. It wasn't as open as it looked on TV. I had no idea it was going to be such a big deal."