As I stated, this isn’t a Constitutional change. Article II just states that the President must be a natural born citizen, but it doesn’t define it. Article I grants congress the authorization to define what is a citizen (thus we have laws like Title 8 that defines citizenship in all sorts of circumstances.)
Queen Nancy Pelosi could simply call an emergency session of congress and quickly pass a law stating anyone born of one US citizen parent, no matter where they are born, age of the parent, nor residency requirements of the parent, is deemed a citizen by birth. I doubt enough on our side would try to stop it (too many yellow politicians) and I would bet President Bush would sign.
No Constitutional change required, simply an update to the US Title Codes defining the parameters for what is a citizen.
I don’t think it would be that easy. If it was, it would have quietly been done already.