Ошибка в добавлении рамки AFNetworking в проект

Добавление рамки AFNetworking в проект Я получил следующие ошибки: -

Undefined symbols for architecture i386:
  "_UTTypeCopyPreferredTagWithClass", referenced from:
      _AFContentTypeForPathExtension in AFURLRequestSerialization.o
  "_UTTypeCreatePreferredIdentifierForTag", referenced from:
      _AFContentTypeForPathExtension in AFURLRequestSerialization.o
  "_kUTTagClassFilenameExtension", referenced from:
      _AFContentTypeForPathExtension in AFURLRequestSerialization.o
  "_kUTTagClassMIMEType", referenced from:
      _AFContentTypeForPathExtension in AFURLRequestSerialization.o
ld: symbol(s) not found for architecture i386
clang: error: linker command failed with exit code 1 (use -v to see invocation)

Я использую xcode 4.5 с sdk iOS 6.0

Ответ 1