diff --git a/tox.ini b/tox.ini
index 316861c..5ba997b 100755
--- a/tox.ini
+++ b/tox.ini
@@ -18,5 +18,7 @@ deps =
 deps =
     nose
     doctest-ignore-unicode
-commands=
+commands =
     nosetests --with-doctest --with-doctest-ignore-unicode isso/ specs/
+install_command =
+    pip install --allow-external ipaddr --allow-unverified ipaddr {opts} {packages}