Can I get some help building HaXml (from hackage) under ghc 6.7?

I'm hoping to get HAppS running under 6.7, and use the new debugger to better understand what's going on under the hood. Eg, when I'm in the h function, I can take a look at the args and just see what types they are. (I am finding building an intuition from the documentation alone to be overwhelming. Too many types, too many instances... total confusion.) HaXMl is a dependendency for happs, that's why I need it.

Anyway building haxml this is what I get. The subject of my message more or less summarizes my confusion.

hartthoma@linuxpt:~/installs/HaXml-1.13.2>runghc Setup.hs build
Setup.hs: Warning: The field "hs-source-dir" is deprecated, please use hs-source-dirs.
Preprocessing library HaXml-1.13.2...
Preprocessing executables for HaXml-1.13.2...
Building HaXml-1.13.2...

src/Text/XML/HaXml.hs:30:7:
    Could not find module `Text.PrettyPrint.HughesPJ':
      it is a member of package pretty-1.0, which is hidden
hartthoma@linuxpt:~/installs/HaXml-1.13.2>ghc-pkg list
/usr/local/lib/ghc-6.7.20070719/package.conf:
    Cabal-1.1.7, base-2.1, directory-1.0, filepath-1.0,
    ghc-6.7.20070719, haskell98-1.0, hpc-0.5, old-locale-1.0,
    old-time-1.0, pretty-1.0, process-1.0, random-1.0, readline-1.0,
    rts-1.0, template-haskell-0.1, unix-2.0
hartthoma@linuxpt:~/installs/HaXml-1.13.2>ghc-pkg list pretty-1.0
/usr/local/lib/ghc-6.7.20070719/package.conf:
    pretty-1.0

hartthoma@linuxpt:~/installs/HaXml-1.13.2>ghc --version
The Glorious Glasgow Haskell Compilation System, version 6.7.20070719


hartthoma@linuxpt:~/installs/HaXml-1.13.2>ghc-pkg describe pretty-1.0
name: pretty
version: 1.0
license: BSD3
copyright:
maintainer: libraries@haskell.org
stability:
homepage:
package-url:
description: This package contains a pretty-printing library.
category:
author:
exposed: True
exposed-modules: Text.PrettyPrint Text.PrettyPrint.HughesPJ
hidden-modules:
import-dirs: $topdir/lib/pretty-1.0
library-dirs: $topdir/lib/pretty-1.0
hs-libraries: HSpretty-1.0
extra-libraries:
extra-ghci-libraries:
include-dirs: $topdir/lib/pretty-1.0/include
includes:
depends: base-2.1
hugs-options:
cc-options:
ld-options:
framework-dirs:
frameworks:
haddock-interfaces: $topdir/share/ghc/doc/html/pretty/pretty.haddock
haddock-html: $topdir/share/ghc/doc/html/pretty
hartthoma@linuxpt:~/installs/HaXml-1.13.2>

hartthoma@linuxpt:~/ProjectRepos/miscAdmin>ghc-pkg list
/usr/local/lib/ghc-6.7.20070719/package.conf:
    Cabal-1.1.7, base-2.1, directory-1.0, filepath-1.0,
    ghc-6.7.20070719, haskell98-1.0, hpc-0.5, old-locale-1.0,
    old-time-1.0, pretty-1.0, process-1.0, random-1.0, readline-1.0,
    rts-1.0, template-haskell-0.1, unix-2.0


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