diff --git a/memcache.py b/memcache.py
index 05b6657..4b90fd6 100644
--- a/memcache.py
+++ b/memcache.py
@@ -895,6 +895,9 @@ def set_multi(self, mapping, time=0, key_prefix='', min_compress_len=0,
         server_keys, prefixed_to_orig_key = self._map_and_prefix_keys(
             six.iterkeys(mapping), key_prefix)
 
+        mapping = dict([(k[1] if type(k) is tuple else k, v)
+                        for k, v in six.iteritems(mapping)])
+
         # send out all requests on each server before reading anything
         dead_servers = []
         notstored = []  # original keys.
diff --git a/tests/test_setmulti.py b/tests/test_setmulti.py
index 756afe8..e1e9e0d 100644
--- a/tests/test_setmulti.py
+++ b/tests/test_setmulti.py
@@ -61,11 +61,11 @@ def tearDown(self):
         socket.socket = self.old_socket
 
     def test_Socket_Disconnect(self):
-        mapping = {'foo': 'FOO', 'bar': 'BAR'}
+        mapping = {'foo': 'FOO', 'bar': 'BAR', (0, 'foobar'): 'FOOBAR'}
         with captured_stderr() as log:
             bad_keys = self.mc.set_multi(mapping)
         self.assertIn('connection closed in readline().', log.getvalue())
-        self.assertEqual(sorted(bad_keys), ['bar', 'foo'])
+        self.assertEqual(sorted(bad_keys), ['bar', 'foo', 'foobar'])
         if DEBUG:
             print('set_multi({0!r}) -> {1!r}'.format(mapping, bad_keys))