diff --git a/AFNetworking/AFHTTPClient.h b/AFNetworking/AFHTTPClient.h
index 3fce876..687b9fd 100644
--- a/AFNetworking/AFHTTPClient.h
+++ b/AFNetworking/AFHTTPClient.h
@@ -139,6 +139,8 @@ extern NSString * AFQueryStringFromParametersWithEncoding(NSDictionary *paramete
 
 /**
  The `AFHTTPClientParameterEncoding` value corresponding to how parameters are encoded into a request body. This is `AFFormURLParameterEncoding` by default.
+
+ @warning JSON encoding will automatically use JSONKit, SBJSON, YAJL, or NextiveJSON, if provided. Otherwise, the built-in `NSJSONSerialization` class is used, if available (iOS 5.0 and Mac OS 10.7). If the build target does not either support `NSJSONSerialization` or include a third-party JSON library, a runtime exception will be thrown when attempting to encode parameters as JSON.
  */
 @property (nonatomic, assign) AFHTTPClientParameterEncoding parameterEncoding;
 
diff --git a/AFNetworking/AFJSONRequestOperation.h b/AFNetworking/AFJSONRequestOperation.h
index 70d003c..7c6a579 100644
--- a/AFNetworking/AFJSONRequestOperation.h
+++ b/AFNetworking/AFJSONRequestOperation.h
@@ -32,6 +32,8 @@
  
  - `application/json`
  - `text/json`
+
+ @warning JSON parsing will automatically use JSONKit, SBJSON, YAJL, or NextiveJSON, if provided. Otherwise, the built-in `NSJSONSerialization` class is used, if available (iOS 5.0 and Mac OS 10.7). If the build target does not either support `NSJSONSerialization` or include a third-party JSON library, a runtime exception will be thrown when attempting to parse a JSON request. 
  */
 @interface AFJSONRequestOperation : AFHTTPRequestOperation {
 @private