RATIONALE: Drugs used in chemotherapy, such as fludarabine and cyclophosphamide, work in different ways to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing. LMB-2 immunotoxin can find cancer cells and kill them without harming normal cells. Giving fludarabine and cyclophosphamide followed by LMB-2 immunotoxin may kill more cancer cells.