I saw part of the third Test yesterday, and Richie Benaud was there. During the lunch break, he commented on an interesting ball in the Windies' first innings. A ball was bowled, and was struck out to long on and was caught in the air. But the batsman was not given out because the umpire had called a no-ball. In a discussion about the meaning of the crease, Richie explained that the no-ball wasn't called because the bowler had overstepped the crease, but because there is another crease - some distance behind the batsman's wicket - which marks an area in which the fielding side is allowed to have only two fielders. At the time the ball was bowled, England had three fielders in this area.
Do you know anything about this rule? I'd never heard of this.