Georg Kindel, chairman of the company better known for producing the Women’s World Awards and the Save The World Awards, said the show will be staged at Schönbrunn Palace at the end of September and feature some of “the biggest artists of our time.”

The story duly made global headlines and started speculation over whether Madonna, U2, Lionel Richie, and Whitney Houston would perform, although Austrian national daily Der Standard is skeptical because the show date has already been moved twice and even the latest details are sketchy at best.

“He gives us nothing concrete,” it said, pointing out there’s still no confirmed date or billing and the event would need special permission to use Schönbrunn.

The palace has been one of the Austrian royal family’s Vienna residences since the early 17th century, and – according to Kindel – it was chosen because Jackson “loved castles.”

Kindel said he expected the event to be in New York, Los Angeles or London, and claimed it had originally been planned for the U.K. capital’s Wembley Stadium for Aug. 29, which would have been Jackson’s 51st birthday.

World Awards press chief Nina Ellend said her company got involved when Michael Jackson’s brother Jermaine visited Vienna for the Save The World Awards, which her company organised at the old Zwentendorf Nuclear Power Plant in Lower Austria. The plant was completed in the mid-’70s but never started, and in a 1978 plebiscite Austria narrowly voted against ever starting it.

Ellend says Jackson, who was picking up a special award on behalf of his late brother, stayed in Vienna for a week. At the end of it, she says he approached Kindel and asked about the possibility of using Schönbrunn for Michael’s tribute show.

At press time she said there’s still no fixed date or confirmed acts, but she expected a further announcement in a few days.

Jackson originally broke the news of the Vienna show Aug. 7, when he appeared on U.S. TV talk show “Larry King Live.”