That strikes me as slightly off, I'd expect it to install an appropriate one from the bootstrap. If not, you'll need http://www.haskell.org/cabal/release/cabal-install-1.20.0.3/cabal-install-1.20.0.3.tar.gz and use the bootstrap install method (bootstrap.sh from the install package). The complication here is that it might pull in dependencies that differ from the Platform, which is why I would expect the Platform install script to do this itself so it can manage the dependencies appropriately.

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