diff --git a/mysnapsession.cabal b/mysnapsession.cabal
--- a/mysnapsession.cabal
+++ b/mysnapsession.cabal
@@ -1,5 +1,5 @@
 Name:                mysnapsession
-Version:             0.3.1
+Version:             0.4
 Synopsis:            Sessions and continuations for Snap web apps
 Description:         This package provides two Snap extensions, implementing
                      sessions as either memory-backed arbitrary types, or as
@@ -30,9 +30,9 @@
   Build-depends:
     base == 4.*,
     bytestring >= 0.9.1 && < 0.10,
-    mtl == 2.*,
-    snap == 0.3.*,
-    snap-core == 0.3.*,
+    mtl == 2.0.*,
+    snap >= 0.4 && < 0.5,
+    snap-core >= 0.4 && < 0.5,
     time >= 1.1 && < 1.3,
     random == 1.0.*,
     containers >= 0.3 && < 0.5,
diff --git a/src/Snap/Extension/Session/Client.hs b/src/Snap/Extension/Session/Client.hs
--- a/src/Snap/Extension/Session/Client.hs
+++ b/src/Snap/Extension/Session/Client.hs
@@ -79,7 +79,7 @@
 getSessionRecord :: (MonadSnap m, Serialize t)
                  => ClientSessionManager t -> m (SessionRecord t)
 getSessionRecord mgr = do
-     cookie <- getCookie "sessionval"
+     cookie <- lookupCookie "sessionval"
      case cookie of
          Nothing -> valToRecord =<< liftIO (clientSessionDefault mgr)
          Just c  -> case decrypt (clientSessionKey mgr) (cookieValue c) of
diff --git a/src/Snap/Extension/Session/Memory.hs b/src/Snap/Extension/Session/Memory.hs
--- a/src/Snap/Extension/Session/Memory.hs
+++ b/src/Snap/Extension/Session/Memory.hs
@@ -16,7 +16,6 @@
 import Control.Applicative
 import Control.Concurrent
 import Control.Monad.Reader
-import Data.List
 import Data.Time.Clock
 import Snap.Extension
 import Snap.Extension.Session
@@ -132,9 +131,9 @@
                    -> m (Maybe (SessionWrapper obj))
 getExistingSession (MemorySessionManager oref sref _) = do
     liftIO (readMVar oref) >>= flip unless mzero
-    cookies <- fmap rqCookies getRequest
     client  <- fmap rqRemoteAddr getRequest
-    case find ((== "sessionid") . cookieName) cookies of
+    ck      <- lookupCookie "sessionid"
+    case ck of
         Nothing  -> return Nothing
         Just sid -> do
             smap <- liftIO $ readMVar sref
diff --git a/src/Snap/SessionUtil.hs b/src/Snap/SessionUtil.hs
--- a/src/Snap/SessionUtil.hs
+++ b/src/Snap/SessionUtil.hs
@@ -4,8 +4,7 @@
 module Snap.SessionUtil where
 
 import Data.Word
-import Snap.Iteratee (enumBS)
-import Snap.Types hiding (redirect)
+import Snap.Types
 import System.Random
 
 import Data.ByteString.Char8 (ByteString)
@@ -20,19 +19,19 @@
     find this one even within the same request.
 -}
 setCookie :: MonadSnap m => Cookie -> m ()
-setCookie cookie = do
-    modifyRequest  req
-    modifyResponse (updateHeaders (M.update cleanRsp "Set-Cookie"))
-    modifyResponse (addCookie cookie)
-  where
-    req | B.null (cookieValue cookie)
-            = \r -> r { rqCookies = cleanReq (rqCookies r) }
-        | otherwise
-            = \r -> r { rqCookies = cookie : cleanReq (rqCookies r) }
-    cleanReq = filter ((/= cookieName cookie) . cookieName)
-    cleanRsp = Just . filter (not . ((cookieName cookie `B.append` "=") `B.isPrefixOf`))
+setCookie cookie = modifyResponse (addResponseCookie cookie)
 
 {-|
+    Retrieves a cookie, looking first in the response map, and if not there,
+    then in the request.  This ensures that the most recently set cookie is
+    retrieved.
+-}
+lookupCookie :: MonadSnap m => ByteString -> m (Maybe Cookie)
+lookupCookie name = do
+    rsp <- getResponse
+    maybe (getCookie name) (return . Just) (getResponseCookie name rsp)
+
+{-|
     Clears a cookie.  This involves setting the cookie to the empty string,
     with an expiration time in the past.
 -}
@@ -51,19 +50,6 @@
     if B.null x
         then pass
         else localRequest (\r -> r {rqPathInfo = B.drop 1 y}) (handler x)
-
-{-|
-    Temporarily here, in the hopes that the type of the original will be fixed
-    in a future version of Snap.
--}
-redirect :: MonadSnap m => ByteString -> m a
-redirect target = do
-    r <- getResponse
-    finishWith
-        $ setResponseCode 302
-        $ setContentLength 0
-        $ modifyResponseBody (const $ enumBS "")
-        $ setHeader "Location" target r
 
 {-|
     Ensure that we're at the top level of a request, and expect that it be a