Other mistake: During the beginning of the freeway chase scene, a "Maximum Speed 65" sign can be seen along the freeway wall in the slow lane that is facing the opposite direction of traffic. Freeway traffic in that lane would only be able to see it in their rear-view mirrors. (01:25:20)
Other mistake: In the scene where Trinity tries to deactivate alarms in the building she types "disable grid nodes 21-48". Then a warning appears on the screen of her laptop which says: 'Disabling nodes 21-48 will disconnect sector 11 (27 nodes)'. However, because of the fact that nodes 21 and 48 are both included in the range, the total number of nodes to be deactivated is 28 (not 27 as written on the screen). (01:43:50)
Other mistake: In the freeway scene, when an agent takes over the black truck, he turns around to go the other way. As he does this, there is a shot from the side of the truck as he turns. In this shot you can see that the front of the truck will easily crash into the wall, but cuts away before it does.
Other mistake: In a scene during a power cut, car headlights also go out.
Answer: This was made just for the trailers. The same part (without the Matrix code) can be seen when Smith says "suprised to see me?" to which Neo replies "No." and puts on his sunglasses before the Burly Brawl.