MELBOURNE, Australia — Newspaper advertisements congratulating the 16-year-old girl who won the latest “Australian Idol” competition made an embarrassing mistake — directing fans to a gay porn Web site. Casey Donovan won the top-rating reality television program and a record contract on Sunday night.

Telecommunications company Telstra, a major sponsor of the program, ran half-page advertisements in newspapers in Sydney and Melbourne on Monday congratulating Casey and directing fans to a Web site.

But anyone calling up the Web site will be confronted by a full frontal nude picture of an American porn star named Casey Donovan with links to sales of his gay porn DVDs and videotapes.

Telstra spokesman Craig Middleton put the gaffe down to “simple human error in the last-minute preparation of the ad.”