COPENHAGEN — Thesp-turned-helmer Liv Ullman, this year’s jury president at Cannes, is prepping a biopic on Norwegian violinist-composer Ole Bull, who died in 1880.The project has been long in the planning with the participation of Norwegian composer and writer Ketil Bjornstad and producer Stein-Roger Bull, head of Norway’s Nordisk Film. Also backed by Ullmann’s longtime collaborator, violinist Arve Tellefsen, the feature will be readied for a 2003 shoot. Ullmann has already started looking for an international cast. Born in Norway, Ole Bull toured Europe and the U.S., where he founded the Norwegian colony of Oleana in Pennsylvania, later living with his American wife in Boston. Ullman’s last feature, “Faithless,” competed at the Cannes Intl. Film Festival in 2000.