RATIONALE: Giving monoclonal antibody therapy, radioimmunotherapy, and chemotherapy before a donor stem cell transplant helps stop the growth of cancer cells and helps stop the patient's immune system from rejecting the donor's stem cells. When the stem cells from a related donor that do not exactly match the patient's blood, are infused into the patient, they may help the patient's bone marrow make stem cells, red blood cells, white blood cells, and platelets. Sometimes the transplanted cells from a donor can also make an immune response against the body's normal cells. Giving tacrolimus and sirolimus before and after transplant may stop this from happening.