The purpose of this study is to test the safety of a transfusion of specialized white cells from your transplant donor's blood, called T-cells, that have been grown and immunized against the CMV virus in the test tube. If the transplant donor is immune to CMV (ie: the donor has antibody to CMV in the blood), the T-cells will be selected and grown from the blood of the transplant donor. However, if the transplant donor is not immune to CMV, or if T-cells from the donor are not readily available, CMV-immune T-cells grown from the blood of another normal donor who is partially matched to the patients tissue type can be used. The transplant physician will explain which of these treatments is available to the patient.