diff --git a/rest_framework/response.py b/rest_framework/response.py
index 0a7d313f4..3ec63f403 100644
--- a/rest_framework/response.py
+++ b/rest_framework/response.py
@@ -6,10 +6,9 @@ The appropriate renderer is called during Django's template response rendering.
 """
 from __future__ import unicode_literals
 import django
-from django.core.handlers.wsgi import STATUS_CODE_TEXT
 from django.template.response import SimpleTemplateResponse
 from django.utils import six
-
+import httplib
 
 class Response(SimpleTemplateResponse):
     """
@@ -81,7 +80,7 @@ class Response(SimpleTemplateResponse):
         """
         # TODO: Deprecate and use a template tag instead
         # TODO: Status code text for RFC 6585 status codes
-        return STATUS_CODE_TEXT.get(self.status_code, '')
+        return httplib[self.status_code]
 
     def __getstate__(self):
         """
diff --git a/rest_framework/serializers.py b/rest_framework/serializers.py
index aef815a88..c7a5de987 100644
--- a/rest_framework/serializers.py
+++ b/rest_framework/serializers.py
@@ -1081,7 +1081,10 @@ class ModelSerializer(Serializer):
                     self.save_object(related)
                 else:
                     # Reverse FK or reverse one-one
-                    setattr(obj, accessor_name, related)
+                    try:
+                        setattr(obj, accessor_name, related)
+                    except ValueError:
+                        getattr(obj, accessor_name).add(*related, bulk=False)
             del(obj._related_data)