RATIONALE: Androgens can cause the growth of prostate cancer cells. Antihormone therapy, such as bicalutamide, may lessen the amount of androgens made by the body. Enzastaurin may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth. It is not yet known whether giving bicalutamide together with enzastaurin is more effective than bicalutamide alone in treating prostate cancer.