What Zeus and CH said - the law at the time of Obama's birth has a specific age and time of residence within the USA requirements for a child to be granted a Natural Born American title. his mother did not meet the age/time within the US requirement. Neither did his father (obviously)
Anyway...
That takes the automatic Natural-Born title from him, So he absolutely needed to be born on US soil (country, military base, embassy, etc.) Otherwise he is a naturalized citizen, and ineligible for POTUS, even if he was naturalized since birth. As I said earlier, I gave up this investigation as a red-herring, and it could continue to be one that will of course be realigned into a racist attack once The Messiah produces the paperwork. It will be interesting to see how this unfolds. It will be even more interesting if Obama wins and then its discovered that the whole race was fraudulent.