diff --git a/tox.ini b/tox.ini
index 2d9d18f85..19120483a 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,5 +1,5 @@
 [tox]
-envlist=du07,du06,du05
+envlist=py24,py25,py26,py27,pypy,du07,du06,du05
 
 [testenv]
 deps=nose
@@ -7,11 +7,32 @@ commands=
     nosetests
     sphinx-build -W -b html -d {envtmpdir}/doctrees doc {envtmpdir}/html
 
+[testenv:py24]
+deps=
+    nose
+    simplejson
+
+[testenv:py25]
+deps=
+    nose
+    simplejson
+
+[testenv:pypy]
+deps=
+    nose
+    simplejson
+
 [testenv:du05]
-deps=docutils==0.5
+deps=
+    nose
+    docutils==0.5
 
 [testenv:du06]
-deps=docutils==0.6
+deps=
+    nose
+    docutils==0.6
 
 [testenv:du07]
-deps=docutils==0.7
+deps=
+    nose
+    docutils==0.7