diff --git a/Control/ContStuff.hs b/Control/ContStuff.hs
--- a/Control/ContStuff.hs
+++ b/Control/ContStuff.hs
@@ -831,18 +831,16 @@
 handle h c = try c >>= either h return
 
 
--- | Throw given exception, if the given computation does not return
--- 'True'.
+-- | Throw given exception, if the given computation returns 'False'.
 
 raiseUnless :: (HasExceptions m, Monad m) => Exception m -> m Bool -> m ()
 raiseUnless ex c = do b <- c; unless b (raise ex)
 
 
--- | Throw given exception, if the given computation does not return
--- 'True'.
+-- | Throw given exception, if the given computation returns 'True'.
 
 raiseWhen :: (HasExceptions m, Monad m) => Exception m -> m Bool -> m ()
-raiseWhen ex c = do b <- c; unless b (raise ex)
+raiseWhen ex c = do b <- c; when b (raise ex)
 
 
 -- | Fail (in the sense of the given transformer), if the given
diff --git a/contstuff.cabal b/contstuff.cabal
--- a/contstuff.cabal
+++ b/contstuff.cabal
@@ -1,5 +1,5 @@
 Name:          contstuff
-Version:       0.6.0
+Version:       0.6.1
 Category:      Control, Monads, Parsing, Text
 Synopsis:      Fast, easy to use CPS-based monads
 Maintainer:    Ertugrul Söylemez <es@ertes.de>
@@ -14,7 +14,10 @@
 Description:
 
   This library implements fast and easy to use CPS-based monad
-  transformers.  Most of the usual monads are implemented.
+  transformers.  Most of the usual monad transformers are implemented,
+  including ChoiceT, ContT, EitherT, MaybeT and StateT.  Because of the
+  design of this library, many other monad transformers are just special
+  cases of those, including e.g. WriterT.
 
 Library
   Build-depends: