In Salzburg, the hills are alive with more than the sound of music. Cross-dressing sparked one evening this season, at a dinner held at the venerable, and generally staid, Goldener Hirsch Hotel. When Arabelle von Karajan hosted a surprise party for her mother, Eliette, widow of the famed conductor and reigning queen of the town, guests were asked to come in drag. “Everybody had to be as amusing as possible,” said the hotel’s unflappable manager, Count Johannes Waldersdorff, who attended in a green wig. Other guests included Dimitri of Yugoslavia (blond for the night), Amyn Aga Khan, Francesca and Franz Hapsburg and assorted other royals. The same group showed up the next night at the splendid Residencz, where Sotheby’s threw the grandest dinner of the season. No one seemed to mind that half the guests worked for the auction house, including Laure de Beauvau-Craon, Simon de Pury and Kristen van Riel.