diff --git a/Data/Convertible/Instances/Time.hs b/Data/Convertible/Instances/Time.hs
--- a/Data/Convertible/Instances/Time.hs
+++ b/Data/Convertible/Instances/Time.hs
@@ -58,15 +58,11 @@
 
 ------------------------------ POSIX and UTC times
 
-#if __GLASGOW_HASKELL__ >= 610
--- instances added in GHC 6.10.3
-#else
 instance Typeable NominalDiffTime where
     typeOf _ = mkTypeName "NominalDiffTime"
 
 instance Typeable UTCTime where
     typeOf _ = mkTypeName "UTCTime"
-#endif
 
 {- Covered under Real a
 instance Convertible Rational POSIXTime where
diff --git a/convertible.cabal b/convertible.cabal
--- a/convertible.cabal
+++ b/convertible.cabal
@@ -1,5 +1,5 @@
 Name: convertible
-Version: 1.0.5
+Version: 1.0.6
 License: LGPL
 Maintainer: John Goerzen <jgoerzen@complete.org>
 Author: John Goerzen
@@ -42,7 +42,8 @@
 
 library
   if flag(splitBase)
-    Build-Depends: base>=3, old-time, time>=1.1.2.4, bytestring, containers, old-locale
+    Build-Depends: base>=3 && <4, old-time, time>=1.1.2.4 && <1.1.3,
+     bytestring, containers, old-locale
   else
     Build-Depends: base<3
   Build-Depends: mtl
@@ -76,4 +77,4 @@
    GHC-Options: -O2
    Extensions: ExistentialQuantification, MultiParamTypeClasses,
                UndecidableInstances, FlexibleInstances,
-               FlexibleContexts, TypeSynonymInstances, CPP
+               FlexibleContexts, TypeSynonymInstances