Calculations were performed for 238U and 232Th blankets for a fusion hybrid reactor. Comparisons between results using ENDF/B-III and ENDF/B-IV cross sections for 238U were made. Corrections to the latter cross-section set were suggested, bringing the computed results close to the reported experimental ones. Computations using ENDF/B-IV 232Th cross sections were found to agree very well with experiment.