1. Patients must have one of the following relapsed/ refractory lymphoid malignancies: Chronic lymphocytic leukemia (CLL), small lymphocytic lymphoma (SLL) or B-prolymphocytic leukemia which has been previously treated with a purine analog, and are not candidates for higher priority clinical studies. Follicular lymphoma, mantle cell lymphoma, lymphoplasmacytoid lymphoma or marginal zone lymphoma which has been previously treated with autologous or allogeneic stem cell transplantation.