diff --git a/Data/Chatty/Hetero.hs b/Data/Chatty/Hetero.hs
--- a/Data/Chatty/Hetero.hs
+++ b/Data/Chatty/Hetero.hs
@@ -38,7 +38,7 @@
   tappend (a :-: b) c = a :-: tappend b c
 
 -- | Typeclass for wrapping a heterogenous list into a Maybe on demand
-class IntoMaybe a ar  where
+class IntoMaybe a ar | a -> ar where
   tjust :: a -> ar
   tnothing :: a -> ar
 instance IntoMaybe Nil Nil where
diff --git a/chatty-utils.cabal b/chatty-utils.cabal
--- a/chatty-utils.cabal
+++ b/chatty-utils.cabal
@@ -10,7 +10,7 @@
 -- PVP summary:      +-+------- breaking API changes
 --                   | | +----- non-breaking API additions
 --                   | | | +--- code changes with no API change
-version:             0.7.1
+version:             0.7.1.2
 
 -- A short (one-line) description of the package.
 synopsis:            Some utilities every serious chatty-based application may need.
@@ -58,7 +58,7 @@
   -- other-extensions:    
   
   -- Other library packages from which modules are imported.
-  build-depends:       base >=4.6 && <4.7, transformers >=0.3 && <0.4, text >=0.11 && <0.12, mtl >=2.1 && <2.2
+  build-depends:       base >=4.6 && <4.8, transformers >=0.3 && <0.4, text >=1.1 && <1.2, mtl >=2.1 && <2.2
   
   -- Directories containing source files.
   -- hs-source-dirs: