The 6-foot-2, 345-pound Jackson played most of the past three seasons with the Atlanta Falcons. He was drafted by the Oakland Raiders in the sixth round (193rd overall) in 1997 and also has played for New Orleans, Green Bay and Jacksonville.

In 2008, Jackson started 15 games and had 23 tackles (21 solo) and two sacks for the Falcons. Jackson was on a list of players accused of using a diuretic, which can serve as a masking agent for steroids, but was not suspended.

Some players said the banned substance Bumetanide was not listed as an ingredient in StarCaps, an over-the-counter weight-loss pill. Jackson filed suit against StarCaps in Alameda County Superior Court in California in November, seeking restitution for any lost salary and damages for "false advertising and unfair business practices."

Jackson also was involved in an uncomfortable scenario with the Falcons in 2007, when then-coach Bobby Petrino cut him in midseason, alienating many of the other players. Jackson wound up with Jacksonville, and when Petrino resigned to take the head coaching job at Arkansas after 13 games, Jackson said: "It just shows his true color, like a coward with a yellow stripe down his back."

When Mike Smith was hired as coach of the Falcons, Jackson was re-signed.

Buchanon, 28, started all 16 games for Tampa Bay last season, intercepting two passes and returning one for a touchdown. The Lions had only one interception by a defensive back in 2008.

A first-round draft pick by the Raiders in 2002, when Oakland lost in the Super Bowl to Tampa Bay, Buchanon started 36 games for the Raiders. He struggled in coverage, though he had 11 interceptions, and was traded to Houston in April 2005 for two draft picks.

After two seasons with the Texans, Buchanon signed with the Bucs as a free agent in 2007.