Early Administration of ATG Followed by Cyclophosphamide, Busulfan and Fludarabine Before a Donor Stem Cell Transplant in Patients With Hematological Cancer

DISEASE CHARACTERISTICS: * Histologically confirmed diagnosis of one of the following: * Chronic myeloid leukemia (CML) * Philadelphia chromosome (Ph)- and/or BCR-ABL-positive disease * In chronic or accelerated phase * Suboptimal response to imatinib mesylate (i.e., no hematologic complete response by 3 months, no major cytogenetic response by 6 months, or no complete cytogenetic response by 1 year) * CML in blastic transformation allowed provided patient achieved complete remission (CR) or second chronic phase after treatment with imatinib mesylate or chemotherapy * Chronic lymphocytic leukemia meeting one of the following criteria: * Rai stage III or IV disease * Rai stage I or II disease that failed standard therapy (i.e., disease is progressing after ≥ 1 course of standard therapy) * Non-Hodgkin lymphoma (NHL) meeting one of the following criteria: * Indolent NHL * Clinical stage III or IV disease or bulky stage II disease (i.e., ≥ one lymphoid mass \> 5 cm in ≥ one dimension) * Relapsed after primary therapy OR is refractory to therapy * Aggressive NHL * Is not considered curable with standard chemotherapy or autologous stem cell transplantation (i.e., relapsed after autologous stem cell transplantation) * Chemotherapy-responsive disease * Multiple myeloma * Durie-Salmon stage II or III disease * Durie Salmon stage I disease allowed provided β2 microglobulin level \> 3 mg/dL * Acute mye…