Schoolboy hacking trams in Poland

According to an article in the Telegraph, a 14-year old boy in Łódź, Poland used an IR transmitter to control the direction of trams in his city, causing at least one tram to derail, injuring 12. When a tram driver in Poland comes to an intersection, the direction in which he travels is controlled by a simple infrared signal, the same system used in a TV remote control.

It's a little scary that by simply programming a universal TV remote control (or using any PDA that has programmable IR capability) that you can control all the trams in a city like Łódź. I ride the tram (streetcar) here in Prague nearly every day (and so do my kids), and I'd hate to think that a kid with a Palm Pilot can derail the trains at will.