TRENTON, N.J. (AP) — Six years after New Jersey Transit won federal approval to install modern safety technology on its commuter rail lines, the project has languished and trains still operate with speed controls developed in the 1950s. The technological divide was underscored last month when a packed NJ Transit train sped to double the 10 mph speed limit and hurtled into Hoboken Terminal, killing a woman on the platform and injuring more than 100 other people. Instead of a sophisticated on-board computer regulating train speeds into the station, NJ Transit relies on an antiquated in-cab signaling system that's designed to alert engineers and stop trains only when they go faster than 20 mph. Even at Hoboken Terminal — where NJ Transit had an exception from positive-train control requirements — experts say an on-board computer tied to the PTC system still would have worked to keep the train within the speed limit. The railroad industry has said installing PTC at train terminals like the one in Hoboken is impractical and cumbersome, given the high volume of trains arriving and departing at what are normally low speeds, as well as the multitude of signals and other infrastructure already in place.