[Haskell-cafe] Hackage: Tarball and package description of package mtl differ

Hi Cafe, I just wanted to install the mtl package for GHC 8.0.1-rc2, but installation failed with Setup: Encountered missing dependencies: transformers ==0.4.* Taking a look at the package description [1], it specifies build-depends: base < 6, transformers >= 0.4 && < 0.6 but the Cabal description in the tarball [2] says build-depends: base < 6, transformers == 0.4.* Strangely, if I execute $ cabal unpack mtl-2.2.1 I obtain a version with the same specification as [1]. Does anybody has an explanation for this? Regards, Björn [1]: http://hackage.haskell.org/package/mtl-2.2.1/mtl.cabal [2]: http://hackage.haskell.org/package/mtl-2.2.1/mtl-2.2.1.tar.gz