Smith will have surgery Thursday on his separated right shoulder. The former No. 1overall draft pick was hurt Sept. 30 against Seattle, and missed six of the 49ers' last nine games before deciding Monday night to undergo surgery to strengthen his still-aching shoulder.
Shaun Hill, a career third-stringer who had never thrown an NFL pass in six seasons before last Sunday, is expected to start Saturday against Cincinnati. Trent Dilfer, Smith's backup for the last two seasons, isn't expected to play because of a concussion.
Weinke has been out of football since the Carolina Panthers released him in March after six seasons, starting 19 games over six seasons. The 35-year-old quarterback played six years of minor league baseball before winning the Heisman Trophy at Florida State in 2000.
Dilfer is doubtful for Saturday's game after getting hurt last week on a hit by Minnesota's Charles Gordon. Drew Olson, who joined the 49ers' practice squad three weeks ago, is the only other quarterback on the roster.