diff --git a/README.rst b/README.rst
index cb3e37dcb..e547a6a8a 100644
--- a/README.rst
+++ b/README.rst
@@ -199,7 +199,10 @@ Configuration
 
   in case your user layout needs to purify username on some weird way.
 
-  Final user name will have an integer suffix in case it's already taken.
+  Final user name will have a random UUID-generated suffix in case it's already
+  taken. The UUID token max length can be changed with the setting::
+
+    SOCIAL_AUTH_UUID_LENGTH = 16
 
 - Backends will store extra values from response by default, set this to False
   to avoid such behavior::
@@ -249,9 +252,10 @@ Configuration
 
       SOCIAL_AUTH_CREATE_USERS = False
 
-  Also, it's possible to associate user accounts that share the same email
-  address if the user entry is unique (that means that if the email is not used
-  by more than one account). This behavior is disabled by default unless::
+  It is also possible to associate multiple user accounts with a single email
+  address as long as the rest of the user data is unique. Set value as True 
+  to enable, otherwise set as False to disable.
+  This behavior is disabled by default (false) unless specifically set::
 
       SOCIAL_AUTH_ASSOCIATE_BY_MAIL = True
 
@@ -496,6 +500,20 @@ credentials in the following way::
     TEST_GOOGLE_USER = 'testing_account@gmail.com'
     TEST_GOOGLE_PASSWORD = 'password_for_testing_account'
 
+
+-------------
+Miscellaneous
+-------------
+
+South_ users should add this rule to enable migrations::
+    try:
+        import south
+        from south.modelsinspector import add_introspection_rules
+        add_introspection_rules([], ["^social_auth\.fields\.JSONField"])
+    except:
+        pass
+
+
 ----
 Bugs
 ----
@@ -597,3 +615,4 @@ Base work is copyrighted by:
 .. _mattucf: https://github.com/mattucf
 .. _Quard: https://github.com/Quard
 .. _micrypt: https://github.com/micrypt
+.. _South: http://south.aeracode.org/
diff --git a/doc/configuration.rst b/doc/configuration.rst
index 5330fe5a9..624897224 100644
--- a/doc/configuration.rst
+++ b/doc/configuration.rst
@@ -110,7 +110,10 @@ Configuration
 
   in case your user layout needs to purify username on some weird way.
 
-  Final user name will have an integer suffix in case it's already taken.
+  Final user name will have a random UUID-generated suffix in case it's already
+  taken. The UUID token max length can be changed with the setting::
+
+    SOCIAL_AUTH_UUID_LENGTH = 16
 
 - Backends will store extra values from response by default, set this to False
   to avoid such behavior::
diff --git a/doc/index.rst b/doc/index.rst
index e1686b3ad..926317cd0 100644
--- a/doc/index.rst
+++ b/doc/index.rst
@@ -19,6 +19,7 @@ Contents:
    signals
    contributions
    testing
+   miscellaneous
    bugs
 
 Indices and tables
diff --git a/doc/miscellaneous.rst b/doc/miscellaneous.rst
new file mode 100644
index 000000000..dcbc1025d
--- /dev/null
+++ b/doc/miscellaneous.rst
@@ -0,0 +1,13 @@
+Miscellaneous
+=============
+
+South_ users should add this rule to enable migrations::
+    try:
+        import south
+        from south.modelsinspector import add_introspection_rules
+        add_introspection_rules([], ["^social_auth\.fields\.JSONField"])
+    except:
+        pass
+
+
+.. _South: http://south.aeracode.org/
diff --git a/social_auth/backends/__init__.py b/social_auth/backends/__init__.py
index 76d3dc715..4eb1f1595 100644
--- a/social_auth/backends/__init__.py
+++ b/social_auth/backends/__init__.py
@@ -65,8 +65,6 @@
 User = UserSocialAuth._meta.get_field('user').rel.to
 # username field max length
 USERNAME_MAX_LENGTH = User._meta.get_field(USERNAME).max_length
-# uuid hex characters to keep while generating unique usernames
-UUID_MAX_LENGTH = 16
 
 # a few settings values
 def _setting(name, default=None):
@@ -192,9 +190,10 @@ def get_random_username():
                 # breaking the field max_length value, this reduces the
                 # uniqueness, but it's less likely to happen repetitions than
                 # increasing an index.
-                if len(username) + UUID_MAX_LENGTH > USERNAME_MAX_LENGTH:
-                    username = username[:USERNAME_MAX_LENGTH - UUID_MAX_LENGTH]
-                name = username + uuid4().get_hex()[:UUID_MAX_LENGTH]
+                uuid_length = getattr(settings, 'SOCIAL_AUTH_UUID_LENGTH', 16)
+                if len(username) + uuid_length > USERNAME_MAX_LENGTH:
+                    username = username[:USERNAME_MAX_LENGTH - uuid_length]
+                name = username + uuid4().get_hex()[:uuid_length]
 
         return final_username
 
diff --git a/social_auth/views.py b/social_auth/views.py
index 6c446ff30..23fcb63b9 100644
--- a/social_auth/views.py
+++ b/social_auth/views.py
@@ -47,9 +47,11 @@ def complete_process(request, backend):
         login(request, user)
         if getattr(settings, 'SOCIAL_AUTH_SESSION_EXPIRATION', True):
             # Set session expiration date if present and not disabled by
-            # setting
+            # setting. Use last social-auth instance for current provider,
+            # users can associate several accounts with a same provider.
             backend_name = backend.AUTH_BACKEND.name
-            social_user = user.social_auth.get(provider=backend_name)
+            social_user = user.social_auth.filter(provider=backend_name) \
+                                          .order_by('-id')[0]
             if social_user.expiration_delta():
                 request.session.set_expiry(social_user.expiration_delta())
         url = request.session.pop(REDIRECT_FIELD_NAME, '') or DEFAULT_REDIRECT