 RATIONALE: Giving low doses of chemotherapy, such as fludarabine, and radiation therapy before a donor stem cell transplant helps stop the growth of cancer cells. It also stops the patients immune system from rejecting the donors stem cells. The donated stem cells may replace the patients immune system and help destroy any remaining cancer cells graft-versus-tumor effect. Sometimes the transplanted cells from a donor can also make an immune response against the bodys normal cells. Giving cyclosporine and mycophenolate mofetil after transplant may stop this from happening. 