When I import a project that started on Xcode 3 on Xcode 4, it ads another set of entries for the icons on the Info.plist file. Something like this:

and some times there is also another entry called "Icon file" (file on the singular, not plural), alone.
Are all these entries required?
Another question: why the launch images Default.png and Default@2x.png are added to the icon sections?
You only need the entry
Icon files(plural) with all your icons (57×57,72×72,114×114,144×144).You may delete the
Icon files (iOS 5)as well as theIcon file(singular).The
Default.png‘s in that section is totally wrong and was maybe placed there because of a bug in Xcode.