No, it does not have a limited slip (positraction) differential. I have an 01S, which has what Porsche call "traction control". The brakes are applied via computer control to the spinning rear wheel to equalize traction.
A simple test to confirm an LSD is to raise the rear of the car, engine off, in neutral. Spin one wheel by hand. The opposite wheel will spin in the same direction if the car has an LSD. If the other wheel spins in the opposite direction, you do not have an LSD.