Any 1080 clip is going to be stored in 60i, because that's how the codec works. It's exactly the same as how the DVX, SDX, SPX, and XL2 store 24p -- it's 23.976 progressive frames per second carried within a 1080i data stream.
So if you import a 1080i/24p clip into your editing program, you'll see that it has 3:2 pulldown applied. If you import a 1080i/24pa clip, you'll see it has 2:3:3:2 pulldown applied. You'd need a 24p-capable editing program that knows and understands 1080/24p pulldown and can reverse the pulldown in order to get at the pure 24p data sequence.
