 Safety evaluations during the study include the collection of adverse events, laboratory tests including blood chemistry and urinalysis, physical examinations, vital signs blood pressure and heart rate and post-void residual urine volume. Over-encapsulated DITROPAN XL, 10 mg tablets once-daily by mouth or over-encapsulated DETROL LA, 4 mg capsules once daily by mouth. The treatment phase of the study runs for 12 weeks. 