special relativity and length contraction

a train (30 m long, at rest) passes through a tunnel (30 m long, at rest). there are lights at either end of the train, the rear one turns on as it enters the tunnel, and the front one, as it exits.

to an observer on the train (in the middle of it), the lights turn on simultaneously, indicating that, from his frame of reference, the train is the same length as the tunnel. to an observer standing in the tunnel, however, it is too late.