[SOLVED] The JKDictionary class is private to JSONKit and should not be used in this fashion

The JKDictionary class is private to JSONKit and should not be used in this fashion

This is a followup question to this In short, I'm making my app iOS 4.3 compatible and using the AFNetworking class version 0.10.1 that supports iOS 4 in my app. This line self.responseJSON = AFJSONDecode(self.responseData, &error); gives me the error bellow. I'm not really familiar with JSON and trying to figure out what this error means.

Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** - [JKDictionary allocWithZone:]: The JKDictionary class is private to JSONKit and should not be used in this fashion.'
*** Call stack at first throw:
(
    0   CoreFoundation                      0x006ef5a9 __exceptionPreprocess + 185
    1   libobjc.A.dylib                     0x018e6313 objc_exception_throw + 44
    2   CoreFoundation                      0x006a7ef8 +[NSException raise:format:arguments:] + 136
    3   CoreFoundation                      0x006a7e6a +[NSException raise:format:] + 58
...
...
26  libdispatch_sim.dylib               0x02888289 _dispatch_call_block_and_release + 16
27  libdispatch_sim.dylib               0x0288acb4 _dispatch_queue_drain + 250
28  libdispatch_sim.dylib               0x0288b2c2 _dispatch_queue_invoke + 49
29  libdispatch_sim.dylib               0x0288b593 _dispatch_worker_thread2 + 261
30  libsystem_c.dylib                   0x90093b24 _pthread_wqthread + 346
31  libsystem_c.dylib                   0x900956fe start_wqthread + 30

The error is from JSONKit.m:

+ (id)allocWithZone:(NSZone *)zone
{
#pragma unused(zone)
    [NSException raise:NSInvalidArgumentException format:@"*** - [%@ %@]: The %@ class is private to JSONKit and should not be used in this fashion.", NSStringFromClass([self class]), NSStringFromSelector(_cmd), NSStringFromClass([self class])];
    return(NULL);
}

With iOS 5 the app is using the line self.responseJSON =[NSJSONSerialization JSONObjectWithData:self.responseData options:0 error:&error]; that works great but ofcourse I can't use this in iOS 4 because NSJSONSerialization isn't supported.

Solution

I ended up replacing the problematic line with this self.responseJSON = [[CJSONDeserializer deserializer] deserialize:self.responseData error:&error];

Used a different class (TouchJSON) just for that line but it works great now.