Sienna Miller signs up for 'G.I. Joe' Actress enlists in Paramount's tentpole By TATIANA SIEGEL Miller Sienna Miller is the first thesp to enlist in Paramount Pictures' big-budget tentpole "G.I. Joe." British actress will play the film's female lead, described as a raven-haired baroness and sexy femme fatale skilled in espionage. Stephen Sommers directs the live-action film based on the Hasbro toys, comicbook and TV series. Paramount, which has set a mid-February start date, has slotted the film for an Aug. 7, 2009, release. Story is set at Brussels-based GIJOE, an acronym for the Global Integrated Joint Operating Entity, and revolves around an international co-ed force of operatives who use high-tech equipment to battle Cobra, an evil org headed by a Scottish arms dealer. Lorenzo di Bonaventura ("Transformers") is producing alongside Hasbro's Brian Goldner. Miller, whose credits include Paramount and di Bonaventura's "Stardust," recently wrapped "Hippie Hippie Shake," "The Edge of Love" and "The Mysteries of Pittsburgh."