 Participants will be randomized to SCH 727965 or a comparator drug bortezomib for mantle cell lymphoma MCL or alemtuzumab for B cell chronic lymphocytic leukemia B CLL. Part 1 of the study will determine the activity of SCH 727965 treatment in participants with MCL and participants with B-CLL. Part 2 of the study will determine the activity of SCH 727965 treatment in participants who experienced disease progression after standard treatment with the comparator drug during Part 1. 