Chennai:Actor-filmmaker Kamal Haasan, who fractured his leg after slipping and falling from the stairs of his office here nearly two weeks ago, is still undergoing treatment in a private hospital, a source said. "He's still expected to stay in the hospital for a few more days. Having already undergone a minor surgery for compound fracture, he's currently kept under observation," a source close to the actor said. The "Vishwaroopam" star has been advised complete rest for at least a month. "The doctors have instructed him to rest for a month. He was all set to commence the second schedule of his upcoming trilingual film from the last week of July. However, due to this unfortunate incident, the shoot has now been postponed to September," the source said. Kamal is directing as well as playing the lead in "Sabash Naidu", which is being made in Tamil, Telugu and Hindi. The film, which is slated to release early next year, has music by maestro Ilayaraja.