No idea how to fix your problem but you can get Cleaner Pro (Show Wallpaper) from the Android Market. This installs an icon that when tapped will hide your icons. They stay hidden until you tap Home or Back. Maybe if the icons are set as hidden when the phone is powered up they won't move. Then again hiding may have no effect. Just hide them before you shut the phone off and they will be hidden when started. The app is free so you could try it.