On our flight back from Japan to Europe via CDG the check-in agent in Tokyo refused to tag our bags through since we had a stopover longer than 12 hours (somehting like 18 hours but overnight). I insisted that the rule was 24 hours but she stood her ground and showed me something in Japanese in her little manual. The Paris staff were suprised and sympathetic but at that point they couldn't do anything and we had to lug our luggage to the hotel and back the next monring.