1. Males with histologically proven adenocarcinoma of the prostate that has progressed (i.e. a minimum of three successive baseline values to document two consecutive rises in Prostate Specific Antigen (PSA) (with the last value 5 ng/mL) taken at least one week apart prior to study entry) despite castration or maintenance of castrate-level testosterone (defined as serum testosterone 50 ng/dL or 1.7 nmol/L), during non-hormonal chemotherapy.