NEW YORK (Reuters) - Not so, says Mariah Carey to rumors that she and Whitney Houston clashed while recording their duet ''When You Believe'' for the upcoming animated film ``The Prince of Egypt.'' Carey tells People magazine she and Houston have ''great chemistry together.'' In fact, the two divas are teaming up again to shoot the ``When You Believe'' video. Carey said, ''It will be a live performance. And no, we don't have a catfight and scratch each other's eyes out.''