It wasn't Jackson's failed physical, but more of a falling out with management (according to Jackson) that led to him being cut. Remember he has been suspended 3 times for drugs, (19 games) but he'd still be an upgrade over what we have at FS right now.
Good article on Jackson' release and his interest in the Skins
Shocked By His Release, Jackson Hopes To Land With Redskins-Pewter Report: Your source for inside and breaking news on the Tampa Bay Buccaneers