problems encountered installing/upgrading Cabal

[Iain Barnett]

I want to install Cabal library 1.6.0.2 on OSX 10.4.11.  
Unfortunately, none of my attempts so far appear to have worked. I  
already had 1.4.0.1 but it wouldn't upgrade when running "cabal  
upgrade", it just hangs.

iainb$ cabal --v
cabal-install version 0.5.1
using version 1.4.0.1 of the Cabal library


first attempt:

iainb$ darcs get http://darcs.haskell.org/cabal-install
iainb$ sudo sh bootstrap.sh

Setup: At least the following dependencies are missing:
Cabal >=1.7.2 && <1.9

Error during cabal-install bootstrap:
Configuring the cabal-install package failed


second attempt; I downloaded the tarball from http://www.haskell.org/ 
cabal/release/cabal-1.6.0.2/Cabal-1.6.0.2.tar.gz:

iainb$ cd Cabal-1.6.0.2/
iainb$ sudo runhaskell Setup configure --prefix=/usr/local/
iainb$ sudo runhaskell Setup build
iainb$ sudo runhaskell Setup install
Installing library in /usr/local/lib/Cabal-1.6.0.2/ghc-6.8.3
Registering Cabal-1.6.0.2...
Reading package info from "dist/installed-pkg-config" ... done.
Saving old package config file... done.
Writing new package config file... done.

iainb$ cabal --v
cabal-install version 0.5.1
using version 1.4.0.1 of the Cabal library

If I run "ghc-pkg list" then it displays:
/usr/local/lib/ghc-6.8.3/package.conf:
     Cabal-1.2.3.0, Cabal-1.6.0.2, ...
/Users/iainb/.ghc/i386-darwin-6.8.3/package.conf:
     Cabal-1.6.0.2, ...


I don't seem to understand what I'm supposed to do, or why 1.4.0.1 is  
the lib being used when it's not in the pkg list. Does anyone know  
how I can get cabal-install to use the new library?

Any help is much appreciated.

Iain