Kafka, 25, was a fourth-round pick of the Philadelphia Eagles in 2010. In 2011, he appeared in four games, completing 11-of-16 passes for 107 yards and two interceptions. Kafka played college football at Northwestern.
The Patriots worked out Kafka in early September after he was waived by the Eagles, but he was out of football in 2012. Once the Patriots' current season ends, Kafka will join the roster for the offseason, and will be in the mix along with backup quarterback Ryan Mallett.
Benard, 27, who worked out for the Patriots in December, played parts of three seasons with the Cleveland Browns as both a defensive end and outside linebacker, depending on their scheme. At 6-foot-2, 256 pounds, he projects to be among the lighter defensive ends for the Patriots.
His best season in Cleveland came in 2010, when he played in 15 games, making two starts. He finished with 28 tackles and 7.5 sacks.
In October 2011, Benard suffered season-ending injuries in a motorcycle accident after leaving practice. He pleaded not guilty to charges of driving under a suspended license and reckless operation of a vehicle.