II. To determine whether the intensification of tyrosine kinase inhibition through the addition of dasatinib in Induction (Days 15-28) and substitution of dasatinib for imatinib during post-Induction therapy, in the context of intensive cytotoxic therapy (according to AALL0031) and a good early response to therapy, will lead to a 3-year event-free survival (EFS) of at least 60% in patients with Ph+ ALL.