Jason Schwartzman, famed for his lead role in 1998's Rushmore, has been tapped to star opposite Molly Shannon and Chris McDonald in the Fox midseason comedy Cracking Up. The project, from writer-producer Mike White (School of Rock, The Good Girl) centers on a psychology graduate student (Schwartzman) who moves into the house of a nutty Beverly Hills family to counsel their introverted youngest son. Schwartzman had been in talks for the role for several months, following the network's decision to release Nicolas D'Agosto, who played his part in the pilot. Sources said the main difficulty in negotiating the deal was Schwartzman's commitment to star opposite Steve Martin and Claire Danes in the feature Shopgirl, which is slated to begin production shortly. The role of the young boy, played in the pilot by Nathan Norton, also is being recast, though Norton remains a contender to continue on in the role, sources said. The stakes are high for Cracking Up. Fox has had little traction with its new fall comedy slate, which includes A Minute With Stan Hooper, Arrested Development, and the already canceled Luis. Another new sitcom planned for Fox's fall slate, The Ortegas, has been pushed back to midseason.