diff --git a/tox.ini b/tox.ini
index 99c7ba23a..de419e155 100644
--- a/tox.ini
+++ b/tox.ini
@@ -26,7 +26,7 @@ deps =
     mechanize
     gadjo
     pyquery
-    mock
+    mock<4
     requests
     vobject
     qrcode