diff --git a/happstack-server.cabal b/happstack-server.cabal
--- a/happstack-server.cabal
+++ b/happstack-server.cabal
@@ -1,5 +1,5 @@
 Name:                happstack-server
-Version:             7.4.6
+Version:             7.4.6.1
 Synopsis:            Web related tools and services.
 Description:         Happstack Server provides an HTTP server and a rich set of functions for routing requests, handling query parameters, generating responses, working with cookies, serving files, and more. For in-depth documentation see the Happstack Crash Course <http://happstack.com/docs/crashcourse/index.html>
 License:             BSD3
diff --git a/src/Happstack/Server/Internal/Types.hs b/src/Happstack/Server/Internal/Types.hs
--- a/src/Happstack/Server/Internal/Types.hs
+++ b/src/Happstack/Server/Internal/Types.hs
@@ -15,7 +15,8 @@
      RsFlags(..), nullRsFlags, contentLength, chunked, noContentLength,
      HttpVersion(..), Length(..), Method(..), canHaveBody, Headers, continueHTTP,
      Host, ContentType(..),
-     readDec', fromReadS, readM, FromReqURI(..)
+     readDec', fromReadS, readM, FromReqURI(..),
+     showRsValidator
     ) where
 
 import Control.Monad.Error (Error(strMsg))
@@ -44,7 +45,6 @@
 import Happstack.Server.Internal.LogFormat (formatRequestCombined)
 import Numeric (readDec, readSigned)
 import System.Log.Logger (Priority(..), logM)
-import Text.Show.Functions ()
 
 -- | HTTP version
 data HttpVersion = HttpVersion Int Int
@@ -223,21 +223,24 @@
 
 instance Show Response where
     showsPrec _ res@Response{}  =
-        showString   "================== Response ================" .
-        showString "\nrsCode      = " . shows      (rsCode res)     .
-        showString "\nrsHeaders   = " . shows      (rsHeaders res)  .
-        showString "\nrsFlags     = " . shows      (rsFlags res)    .
-        showString "\nrsBody      = " . shows      (rsBody res)     .
-        showString "\nrsValidator = " . shows      (rsValidator res)
+        showString   "================== Response ================"                    .
+        showString "\nrsCode      = " . shows      (rsCode res)                        .
+        showString "\nrsHeaders   = " . shows      (rsHeaders res)                     .
+        showString "\nrsFlags     = " . shows      (rsFlags res)                       .
+        showString "\nrsBody      = " . shows      (rsBody res)                        .
+        showString "\nrsValidator = " . shows      (showRsValidator (rsValidator res))
     showsPrec _ res@SendFile{}  =
-        showString   "================== Response ================" .
-        showString "\nrsCode      = " . shows      (rsCode res)     .
-        showString "\nrsHeaders   = " . shows      (rsHeaders res)  .
-        showString "\nrsFlags     = " . shows      (rsFlags res)    .
-        showString "\nrsValidator = " . shows      (rsValidator res).
-        showString "\nsfFilePath  = " . shows      (sfFilePath res) .
-        showString "\nsfOffset    = " . shows      (sfOffset res)   .
+        showString   "================== Response ================"                    .
+        showString "\nrsCode      = " . shows      (rsCode res)                        .
+        showString "\nrsHeaders   = " . shows      (rsHeaders res)                     .
+        showString "\nrsFlags     = " . shows      (rsFlags res)                       .
+        showString "\nrsValidator = " . shows      (showRsValidator (rsValidator res)) .
+        showString "\nsfFilePath  = " . shows      (sfFilePath res)                    .
+        showString "\nsfOffset    = " . shows      (sfOffset res)                      .
         showString "\nsfCount     = " . shows      (sfCount res)
+
+showRsValidator :: Maybe (Response -> IO Response) -> String
+showRsValidator = maybe "Nothing" (const "Just <function>")
 
 -- what should the status code be ?
 instance Error Response where
diff --git a/src/Happstack/Server/Response.hs b/src/Happstack/Server/Response.hs
--- a/src/Happstack/Server/Response.hs
+++ b/src/Happstack/Server/Response.hs
@@ -35,6 +35,7 @@
 import qualified Data.Text.Lazy                  as LT
 import qualified Data.Text.Lazy.Encoding         as LT
 import           Happstack.Server.Internal.Monads         (FilterMonad(composeFilter))
+import           Happstack.Server.Internal.Types
 import           Happstack.Server.Types          (Response(..), Request(..), nullRsFlags, getHeader, noContentLength, redirect, result, setHeader, setHeaderBS)
 import           Happstack.Server.SURI           (ToSURI)
 import qualified Text.Blaze.Html                 as Blaze
@@ -315,18 +316,18 @@
 -- | A nicely formatted rendering of a 'Response'
 prettyResponse :: Response -> String
 prettyResponse res@Response{}  =
-    showString   "================== Response ================" .
-    showString "\nrsCode      = " . shows      (rsCode res)     .
-    showString "\nrsHeaders   = " . shows      (rsHeaders res)  .
-    showString "\nrsFlags     = " . shows      (rsFlags res)    .
-    showString "\nrsBody      = " . shows      (rsBody res)     .
-    showString "\nrsValidator = " $ show       (rsValidator res)
+    showString   "================== Response ================"       .
+    showString "\nrsCode      = " . shows      (rsCode res)           .
+    showString "\nrsHeaders   = " . shows      (rsHeaders res)        .
+    showString "\nrsFlags     = " . shows      (rsFlags res)          .
+    showString "\nrsBody      = " . shows      (rsBody res)           .
+    showString "\nrsValidator = " $ showRsValidator (rsValidator res)
 prettyResponse res@SendFile{}  =
-    showString   "================== Response ================" .
-    showString "\nrsCode      = " . shows      (rsCode res)     .
-    showString "\nrsHeaders   = " . shows      (rsHeaders res)  .
-    showString "\nrsFlags     = " . shows      (rsFlags res)    .
-    showString "\nrsValidator = " . shows      (rsValidator res).
-    showString "\nsfFilePath  = " . shows      (sfFilePath res) .
-    showString "\nsfOffset    = " . shows      (sfOffset res)   .
+    showString   "================== Response ================"                    .
+    showString "\nrsCode      = " . shows      (rsCode res)                        .
+    showString "\nrsHeaders   = " . shows      (rsHeaders res)                     .
+    showString "\nrsFlags     = " . shows      (rsFlags res)                       .
+    showString "\nrsValidator = " . shows      (showRsValidator (rsValidator res)) .
+    showString "\nsfFilePath  = " . shows      (sfFilePath res)                    .
+    showString "\nsfOffset    = " . shows      (sfOffset res)                      .
     showString "\nsfCount     = " $ show       (sfCount res)