diff --git a/pkgs/top-level/python-packages.nix b/pkgs/top-level/python-packages.nix
index ad0199d2696..67f722ff7d7 100644
--- a/pkgs/top-level/python-packages.nix
+++ b/pkgs/top-level/python-packages.nix
@@ -1750,14 +1750,14 @@ let
 
 
   colander = buildPythonPackage rec {
-    name = "colander-1.0b1";
+    name = "colander-1.0";
 
     src = pkgs.fetchurl {
       url = "http://pypi.python.org/packages/source/c/colander/${name}.tar.gz";
-      md5 = "89f2cf4b5c87d43f7917d6a0d4872e6a";
+      md5 = "058576123da7216288c079c9f47693f8";
     };
 
-    propagatedBuildInputs = with self; [ self.translationstring ];
+    propagatedBuildInputs = with self; [ self.translationstring self.iso8601 ];
 
     meta = {
       maintainers = [