Puzzle Four Liter

This puzzle is a nice and simple one. It appears in the sequel of the movie "Die Hard": NYPD officer John McClane and store owner Zeus Carver find themselves in quite a predicament. A psychopath is setting off bombs all over New York. McClane and Zeus find another bomb in Central Park, and to defuse it, they have to solve a mystery. The bomb is in a briefcase containing a precise electronic scale. McClane and Zeus have a 5-liter jug and a 3-liter jug. They are standing next to a fountain from which they can draw as much water as they want. They have 5 minutes to put one of the jugs with exactly 4 liters of water on the scale or the bomb will explode. How do you get exactly 4 liters of water into one of the jugs?

[Try to click on the water taps and arrows on the figure below to solve the problem.]