diff --git a/CHANGES.md b/CHANGES.md
index 150f06c7..8ae244f8 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -23,6 +23,7 @@
 * Update SimpleJSON library 3.7.3 to 3.8.0 (a37a9bd)
 * Update Tornado Web Server 4.2 to 4.3.dev1 (1b6157d)
 * Update change to suppress reporting of Tornado exception error 1 to updated package (ref:hacks.txt)
+* Update fix for API response header for JSON content type and the return of JSONP data to updated package (ref:hacks.txt)
 
 
 ### 0.10.0 (2015-08-06 11:05:00 UTC)
diff --git a/tornado/web.py b/tornado/web.py
index b6197ce7..039853d5 100644
--- a/tornado/web.py
+++ b/tornado/web.py
@@ -692,7 +692,10 @@ class RequestHandler(object):
                 message += ". Lists not accepted for security reasons; see http://www.tornadoweb.org/en/stable/web.html#tornado.web.RequestHandler.write"
             raise TypeError(message)
         if isinstance(chunk, dict):
-            chunk = escape.json_encode(chunk)
+            if 'unwrap_json' in chunk:
+                chunk = chunk['unwrap_json']
+            else:
+                chunk = escape.json_encode(chunk)
             self.set_header("Content-Type", "application/json; charset=UTF-8")
         chunk = utf8(chunk)
         self._write_buffer.append(chunk)