diff --git a/tox.ini b/tox.ini
index a078c8fe1b..23aca8e84d 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,6 +1,10 @@
 [tox]
+minversion = 1.6
 envlist = pyflakes,pep8
 
+[testenv]
+install_command = pip install -U {opts} {packages}
+
 [testenv:pyflakes]
 deps = pyflakes
 commands = pyflakes modules setup.py