diff --git a/tox.ini b/tox.ini
index 553ff56..f11d8c5 100644
--- a/tox.ini
+++ b/tox.ini
@@ -75,7 +75,7 @@ basepython = python2.6
 deps = -egit+http://git.openstack.org/cgit/openstack/ceilometer@stable/havana#egg=ceilometer
 changedir = {envdir}/src/ceilometer
 commands = tox -e py26 --notest  # ensure a virtualenv is built
-           {envdir}/src/ceilometer/.tox/py26/bin/pip install {toxinidir}  # install pecan-dev
+           {envdir}/src/ceilometer/.tox/py26/bin/pip install -U {toxinidir}  # install pecan-dev
            tox -e py26
 
 [testenv:ceilometer-tip]
@@ -83,7 +83,7 @@ basepython = python2.6
 deps = -egit+http://git.openstack.org/cgit/openstack/ceilometer#egg=ceilometer
 changedir = {envdir}/src/ceilometer
 commands = tox -e py26 --notest  # ensure a virtualenv is built
-           {envdir}/src/ceilometer/.tox/py26/bin/pip install {toxinidir}  # install pecan-dev
+           {envdir}/src/ceilometer/.tox/py26/bin/pip install -U {toxinidir}  # install pecan-dev
            tox -e py26
 
 [testenv:ironic-tip]
@@ -91,7 +91,7 @@ basepython = python2.7
 deps = -egit+http://git.openstack.org/cgit/openstack/ironic#egg=ironic
 changedir = {envdir}/src/ironic
 commands = tox -e py27 --notest  # ensure a virtualenv is built
-           {envdir}/src/ironic/.tox/py27/bin/pip install {toxinidir}  # install pecan-dev
+           {envdir}/src/ironic/.tox/py27/bin/pip install -U {toxinidir}  # install pecan-dev
            tox -e py27
 
 [testenv:pep8]