I'm a direct descendant of Macajah Cage Miller, who married a Mary Jane "Polly" Garrard. He was the son of William Miller (haven't been able to find anything on his wife). Macajah also had a brother, Robert. I have seen his name spelled with an i as you have spelled it, "Micajah." I have a lot of information on his descendants.
I realize you posted this over a decade ago, but I'm hoping you or someone may have additional information of William Miller.