diff --git a/django/contrib/contenttypes/generic.py b/django/contrib/contenttypes/generic.py
index 0504592ebb..c294f74500 100644
--- a/django/contrib/contenttypes/generic.py
+++ b/django/contrib/contenttypes/generic.py
@@ -59,7 +59,7 @@ class GenericForeignKey(object):
 
     def __get__(self, instance, instance_type=None):
         if instance is None:
-            raise AttributeError, u"%s must be accessed via instance" % self.name
+            return self
 
         try:
             return getattr(instance, self.cache_attr)
@@ -183,7 +183,7 @@ class ReverseGenericRelatedObjectsDescriptor(object):
 
     def __get__(self, instance, instance_type=None):
         if instance is None:
-            raise AttributeError, "Manager must be accessed via instance"
+            return self
 
         # This import is done here to avoid circular import importing this module
         from django.contrib.contenttypes.models import ContentType