Xcode升級到4.4後，Jsonkit中的警告

Direct access to objective-c's isa is deprecated in favor of object_setClass() and object_getClass()

object->isa 替換為 object_getClass(object)
keyObject->isa 替換為 object_getClass(keyObject)
(id)keys[idx]->isa 替換為 object_getClass((id)keys[idx])

array->isa = _JKArrayClass; 改成 object_setClass(array, _JKArrayClass);

dictionary->isa = _JKDictionaryClass; 改成 object_setClass(dictionary, _JKDictionaryClass);

format specifies type 'unsigned long' but the argument has type 'nsuinteger' (aka 'unsigned int')
給變數增加(unsigned long)進行類型轉換