actualy, it's farily common in US wiring to have a single white neutral wire for 2 breakers. Basicaly what you have is two 120v hot legs that give you a 240v circut for powering large devices like dryers, A/C units, stoves, etc.

however, having an improperly wired hot leg on a normal outlet is bad! 240v cirucuts should use a different outlet plug.