This is the second time that happend to me. If I totaly discharge iPod's battery it will not start after I charge it.
First time it happend I tried to charge iPod overnight. I'm not sure, but I think it only works with real charger not through USB or FireWire connection to PC. Apple doesn't mention this on support page. But it worked.
Today I tried another thing. I charged iPod in the car for half an hour then I reset it. It works also.