Application.LoadLevel() How to know the loading percentage?

I have to load a large scene on Iphone platform,so it took nearly about 10 sec to finish loading. Can know the loading percentage,so I can make a loading Bar. Now I have to make something rotate,rotate... while loading the level. Sorry for my english,thank you very much.

This is not possible right now, the level loading operation does not provide any progress information, so you have to stay with your loading bar.

LoadLevel.LoadLevelAsync() seems does not work, can you give me some demo codes?
Thank you!