How can you determine who are citizens by act of law if you do not first define by law who are not? In otherwords, how can you legally define a naturalized citizen without first defining who is a natural born citizen? And that is what Congress has done over the years, defining citizens at birth as opposed to naturalized citizens. So why shouldn't their definition apply to presidential candidates?
My answer to your question is here:
http://www.freerepublic.com/focus/bloggers/2144085/posts?page=26#26