I updated project to Xcode 5 and enabled modules in build settings.
However, I see compiler error Unexpected \'@\' in program when I use @import.>
From the comment of @hw731 I think you use badly @import :
old syntax to import framework :
#import
but now, you can use the new syntax :
@import UIKit;
you need to enable theses modules to use the keyword @import (it's enable by default when you create a new project with Xcode 5) :

Have a look here.