diff --git a/tox.ini b/tox.ini
index 73bec1f..89f1fa4 100644
--- a/tox.ini
+++ b/tox.ini
@@ -6,7 +6,7 @@ envlist =
 [testenv]
 usedevelop = True
 deps =
-    mock
+    mock<1.1.0
     nose
 commands =
     python setup.py test -q