you may have seen the following error message: Storyboards are unavailable on iOS 4.3 and prior
but, however, updating Xcode to the latest version (4.3.1) also does not help.
Here's the trick to change the design for the storyboard: iOS5 Storyboard error: Storyboards are not available in iOS 4.3 and earlier
>Open XXXXXX.storyboard > >Open Identity and Type tag in your right view of Xcode. > >Set the value of Development in Document Versioning to "Xcode 4.2" (my default value is "Default Version (Xcode 4.1)". > >Change the value of Deployment from Project SDK Version (iOS 5.0) to iOS 5.0, then back to Project SDK Version (iOS 5.0)
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