diff --git a/README.org b/README.org
--- a/README.org
+++ b/README.org
@@ -81,6 +81,10 @@
 
 * Release Notes
 
+** 0.4 series
+
+- 0.4.0 :: Update conduit to 0.4.0, which is incompatible with earlier versions.
+
 ** 0.3 series
 
 - 0.3.2 :: Add awsRef / simpleAwsRef request variants for those who prefer an =IORef= over a =Data.Attempt.Attempt= value.
diff --git a/aws.cabal b/aws.cabal
--- a/aws.cabal
+++ b/aws.cabal
@@ -6,7 +6,7 @@
 -- The package version. See the Haskell package versioning policy
 -- (http://www.haskell.org/haskellwiki/Package_versioning_policy) for
 -- standards guiding when and how versions should be incremented.
-Version:             0.4.0
+Version:             0.4.0.1
 
 -- A short (one-line) description of the package.
 Synopsis:            Amazon Web Services (AWS) for Haskell
@@ -150,7 +150,7 @@
                        old-locale           == 1.*,
                        text                 >= 0.11,
                        time                 >= 1.1.4   && < 1.5,
-                       transformers         >= 0.2.2.0 && < 0.3,
+                       transformers         >= 0.2.2.0 && < 0.4,
                        utf8-string          == 0.3.*,
                        xml-conduit          >= 0.7.0