Donor Stem Cell Transplant in Treating Patients With Relapsed Hematologic Malignancies or Secondary Myelodysplasia Previously Treated With High-Dose Chemotherapy and Autologous Stem Cell Transplant

DISEASE CHARACTERISTICS: * Histologically confirmed hematologic malignancies: * Chronic lymphocytic leukemia (CLL) or prolymphocytic leukemia (PLL) * Absolute lymphocytosis of \> 5,000/μL * Lymphocytes must appear morphologically mature with \< 55% prolymphocytes (CLL) * Patients with \> 55% prolymphocytes are considered as having PLL * Lymphocyte phenotype with expression of CD20, CD19, and CD5 (CLL) * Non-Hodgkin lymphoma * Any WHO classification of histologic subtype * Core biopsies acceptable for primary diagnosis and immunophenotyping * Bone marrow biopsies as sole means of diagnosis not allowed for follicular lymphoma * Hodgkin lymphoma * Any WHO classification of histologic subtype * Core biopsies acceptable for primary diagnosis and immunophenotyping * Bone marrow biopsy is required * Multiple myeloma * Patients must have active disease requiring treatment (Durie-Salmon stage I-III) * Acute myeloid leukemia * Must have \< 10% bone marrow blasts and no circulating blasts * Myelodysplastic syndrome (MDS) * MDS as define by WHO criteria * Must have \< 10% marrow blasts * Relapsed or progressive disease or myelodysplasia ≥ 6 months after prior high-dose chemotherapy with autologous hematopoietic cell support * Prior syngeneic transplantation allowed * Healthy donor meeting one of the following criteria: * HLA-identical sibling (6/6) * Serologic typing for class I (A, B) and molecular…