OUTLINE: REDUCED-INTENSITY CONDITIONING: Patients receive rituximab intravenously (IV) followed by indium In-111 ibritumomab tiuxetan IV over 10 minutes on day -21 and rituximab IV followed by yttrium Y 90 ibritumomab tiuxetan IV over 10 minutes on day -14. Patients also receive fludarabine phosphate IV on days -9 to -5 and melphalan IV on day -4.