diff --git a/requirements.txt b/requirements.txt
index 38c8b79..74d28c4 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -16,7 +16,7 @@
 python-keystoneclient
 python-glanceclient
 oktest
-iso8601==0.1.10
+iso8601
 scipy
 numpy
 matplotlib