[Haskell-beginners] installing text-icu on Mac OSX with cabal

[7stud]

I want to try unicode with haskell, and the Data.Text docs say I need text-icu. This is what I tried:

Mac OS X 10.6.8

~/haskell_programs$ cabal update
Downloading the latest package list from hackage.haskell.org

~/haskell_programs$ cabal install text-icu
Resolving dependencies...
Downloading text-icu-0.6.3.5...
Configuring text-icu-0.6.3.5...
cabal: Missing dependencies on foreign libraries:
* Missing C libraries: icui18n, icudata, icuuc
This problem can usually be solved by installing the system packages that
provide these libraries (you may need the "-dev" versions). If the libraries
are already installed but in a non-standard location then you can use the
flags --extra-include-dirs= and --extra-lib-dirs= to specify where they are.
Failed to install text-icu-0.6.3.5
cabal: Error: some packages failed to install:
text-icu-0.6.3.5 failed during the configure step. The exception was:
ExitFailure 1
I found a post by a Windows user who had the same problem. Do I really need to go out and install those C libraries? Or are they 'misplaced' somewhere on my system?

Thanks.