Standard Library Haddock-Interfaces?

Consider this:

  module M (Monoid(..)) where
  {
  import Control.Monad.Monoid;
  }

I'd like Haddock to show documentation for Monoid in module M (for 
instance). Are there standard Haddock-interfaces for the standard 
libraries? Or should I generate them myself, and if so, should I use the 
ghc6-libsrc package, or should I check out some tag in CVS?

-- 
Ashley Yakeley, Seattle WA