 This randomized phase III trial studies how well imatinib mesylate and combination chemotherapy work in treating patients with newly diagnosed Philadelphia chromosome positive acute lymphoblastic leukemia. Imatinib mesylate may stop the growth of cancer cells by blocking some of the enzymes needed for cell growth. Drugs used in chemotherapy, work in different ways to stop the growth of cancer cells, either by killing the cells, by stopping them from dividing, or by stopping them from spreading. Giving imatinib mesylate and combination chemotherapy may work better in treating patients with Philadelphia chromosome positive acute lymphoblastic leukemia. 