The San Francisco 49ers signed veteran cornerback Walt Harris on Wednesday, adding depth to a young secondary. Harris has played 10 NFL seasons with three teams, spending the last two years with the Washington Redskins after earlier stints in Chicago and Indianapolis. He started 12 games for the Redskins last season despite injuries, but was released Friday when they needed to get under the salary cap. "I'm definitely ready to come in and help," Harris said. "I've been a young guy before, and I know how I thought as a young guy. I was surrounded by a lot of veteran leadership, and that helped me out a whole lot. I just really want to return the favor."