[xmonad] xmonad-contrib fails to build

[Tony Morris]

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Hello,
xmonad-contrib 0.9.1 is failing to build with GHC 6.12.1. I was
wondering if upgrading to GHC 6.12.3 would fix this. If not, then what
other options are there?

$ cabal install xmonad-contrib
Resolving dependencies...
Configuring xmonad-contrib-0.9.1...
Preprocessing library xmonad-contrib-0.9.1...
Building xmonad-contrib-0.9.1...
[  1 of 180] Compiling XMonad.Util.Replace ( XMonad/Util/Replace.hs,
dist/build/XMonad/Util/Replace.o )

XMonad/Util/Replace.hs:1:0:
    Warning: Module `Prelude' is deprecated:
               You are using the old package `base' version 3.x.
               Future GHC versions will not support base version 3.x. You
               should update your code to use the new base version 4.x.
[  2 of 180] Compiling XMonad.Util.CustomKeys (
XMonad/Util/CustomKeys.hs, dist/build/XMonad/Util/CustomKeys.o )

XMonad/Util/CustomKeys.hs:80:23:
    Not in scope: data constructor `Reader'
cabal: Error: some packages failed to install:
xmonad-contrib-0.9.1 failed during the building phase. The exception was:
ExitFailure 1

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