 This study is designed to determine the number of donor lymphocytes that can be given to recipients of haploidentical stem cell transplants after depletion of recipient-reactive T lymphocytes by ex-vivo treatment with a fixed dose of RFT5-dgA immunotoxin, and will result in a rate of Grade IIIIV GVHD of 25, to analyze immune reconstitution in these patients, and to measure their overall and disease free survival, at 100 days and at 1 year. 