A title may appear twice on IMDb if there was a short later developed into a full length feature. For example, the film Bottle Rocket (1994) is not the same as Bottle Rocket (1996), even if at first glance they look similar. The first one was a 13 minute short, which was later expanded into the 1996 feature.
For other examples of shorts later turned into full-length features, see: Some Folks Call It a Sling Blade (1994), which became Sling Blade (1996); Jimmy Zip (1996), later remade as Jimmy Zip (1999), and Cashback (2004), later expanded to Cashback (2006).