 - Arm II: Patients receive oral imatinib mesylate twice daily in the absence of disease progression or unacceptable toxicity. Patients experiencing disease progression, intolerance to imatinib mesylate, lack of major cytogenetic response at 12 weeks, or 30 absolute reduction in Philadelphia chromosome-positive metaphases at 12 weeks cross over to arm I after a 1-week washout period. After crossover, patients receive oral BMS-354825 twice daily in the absence of further disease progression or unacceptable toxicity. 