Total Marrow and Total Lymph Node Irradiation, Fludarabine, and Melphalan Followed By Donor Stem Cell Transplant in Treating Patients With Advanced Hematological Cancer That Has Not Responded to Treatment

RATIONALE: Giving total marrow and total lymph node irradiation together with low doses of chemotherapy before a donor stem cell transplant helps stop the growth of cancer cells. It may also stop the patient's immune system from rejecting the donor's stem cells. The donated stem cells may replace the patient's immune cells and help destroy any remaining cancer cells (graft-versus-tumor effect). PURPOSE: This phase I trial is studying the side effects and best dose of total marrow and total lymph node irradiation when given together with fludarabine and melphalan followed by donor stem cell transplant in treating patients with advanced hematological cancer that has not responded to treatment.