...and I'm back to the error regarding the shadowing of network  pakage

ovidiu@thinkpad ~ $ cabal install cabal-install
Resolving dependencies...
Downloading cabal-install-1.20.0.2...
Configuring cabal-install-1.20.0.2...
Warning: This package indirectly depends on multiple versions of the same
package. This is highly likely to cause a compile failure.
package HTTP-4000.2.8 requires network-2.4.1.2
package cabal-install-1.20.0.2 requires network-2.4.1.2
Building cabal-install-1.20.0.2...
Preprocessing executable 'cabal' for cabal-install-1.20.0.2...
<command line>: cannot satisfy -package-id network-2.4.1.2-fc99093587d92370c7febe034504fb40:
    network-2.4.1.2-fc99093587d92370c7febe034504fb40 is shadowed by package network-2.4.1.2-040cee5ece44014a8574cb3f87b1eec4
    (use -v for more information)
Failed to install cabal-install-1.20.0.2
cabal: Error: some packages failed to install:
cabal-install-1.20.0.2 failed during the building phase. The exception was:
ExitFailure 1