In prevention of GVHD, the patient will also receive medicine called FK506 as well as low dose methotrexate. The FK506 will be given intravenously (through the vein) initially starting 2 days before the transplant and later by mouth (when they are able to take oral medications). This drug will be given each day for several weeks. Four doses of low dose methotrexate will be given intravenously. The methotrexate will be given on the day after the transplant, 3, 6 and 11 days after the transplant. If the GVHD cannot be controlled with FK506, other medicines may need to be given. Your doctor will describe these medicines at that time.