ILCannedURLProtocol - how to test error status codes

[laucel]

I'm using AFNetoworking and I'm tying to test a response containing, for example, a 400 status code. I'm setting status code like this:

[ILCannedURLProtocol setCannedStatusCode:400];

and the method under test correctly calls his error block but I'm getting a

AFNetworking Expected status code in (200-299), got 400

In your demo you always receive a 200 code, and get the error code from json, is that the only way?
Thanks.