Mapping bad JSON RestKit

Question

I developing some app with HTTP requests. All responses from server was great. And easy to mapping. But the last one is very bad.

 "positions": {
                   "google": {
                              "some not mutable key1": 3,
                              "some not mutable key2": 12,
                              "some not mutable key3": 5,
                              "some not mutable key4": 7
                              }
                  }
     }

I need to mapping this response in the NSArray or NSDictionary to work with them, but I can't write something like this:

    NSDictionary *mappingDictionary = @{

                                    @"attrs.positions.google" : @"googleArray"

                                    };



    RKObjectMapping *taskMapping = [RKObjectMapping mappingForClass:[SMPosition class]];
    [taskMapping addAttributeMappingsFromDictionary:mappingDictionary];