Cabal says parsec-3.1.1 not available, ghc-pkg says it is available

I am lost. Cabal-install says 'there is no available version of parsec that satisfies ==3.1.1', but ghc-pkg says I have this parsec version installed. mypkg$ cabal install --constraint=parsec==3.1.1 Resolving dependencies... cabal: There is no available version of parsec that satisfies ==3.1.1 mypkg$ ghc-pkg list parsec /usr/local/lib/ghc-7.0.1/package.conf.d /home/bla/.ghc/i386-linux-7.0.1/package.conf.d parsec-2.1.0.1 parsec-3.1.1 mypkg$ cabal --version cabal-install version 0.8.2 using version 1.8.0.6 of the Cabal library Maybe parsec is somehow installed incompletely? 'ghc-pkg check' shows no error.