The Jaguars also finalized the trade Monday, meaning Smith passed his physical with the Packers. Jacksonville received a conditional seventh-round draft pick from Green Bay.
Jackson, a third-round draft pick by Atlanta in 2008, has played in 31 games. He spent the preseason with the Falcons and was waived in final cuts.
He has 64 career tackles, seven passes defended and an interception. Jackson was a three-year starter at LSU and finished his college career with 142 tackles and eight interceptions.