iPad App folders disappeared - iOS 4.2 Bug

While the folder management feature on iOS 4.2 for iPad is without doubt very useful, there is a bug that causes folders to "disappear". After updating the iPad to the latest iOS 4.2 software update, a number of users have reported this similar issues. I had organized hundreds of apps into folders on iTunes. And click "Apply" buton. After about 15 minutes, the folders I created are all gone. Here