Don Chater, most of my info on Lansky comes from Robert Lacey's outstanding biography, "Little Man - Meyer Lansky and the Gangster Life," one of the very few gangster bios that's well researched and accurate.
Juventus: Yes, Lansky spent three months in a jail in Saratoga Springs, NY in the early Fifties on a minor gambling charge. Although he'd been arrested several times as a young man, and was arrested several times later, this was the only time he actually served a prison sentence.