I came to the post through a Google search, so I'm late to comment, but I felt compelled to mention that "led" is an Americanization, like "color", "pedophile", etc. I'm Canadian and, generally, I've been taught to use "led" rather than "lead" (presumably due to the proximity of Canada to the US), but, as riverfox mentioned, the latter is an acceptable form of the past tense elsewhere in the world.