I think what you're referring to is what we call positive train control. If a locomotive engineer is about to run through a red signal, for whatever reason, and he's not slowing down or stopping, a system will override a locomotive and bring the locomotive to a stop. Or if he's about to take a switch that is in reverse position, the locomotive will come to a stop as well.
That technology is currently being looked at in the United States. The U.S. Congress, through the Rail Safety Improvement Act, required all railways operating on mixed traffic, that being freight and passenger and where there is highly toxic material, to implement positive train control by 2015. However, the cost-benefit ratio is currently 22 to 1. They're working all the bugs out of that system. In the meantime, we're waiting to see how they're going to manage that system. We're going to look at it to possibly eventually do the same implementation in Canada.