$ cabal install binary-shared
Resolving dependencies...
Configuring binary-shared-0.8...
Preprocessing library binary-shared-0.8...
Building binary-shared-0.8...
[1 of 1] Compiling Data.Binary.Shared ( src/Data/Binary/Shared.hs,
dist/build/Data/Binary/Shared.o )
Registering binary-shared-0.8...
Installing library in /home/anders/.cabal/lib/binary-shared-0.8/ghc-6.12.1
Registering binary-shared-0.8...
$ ghc-pkg recache
ghc-pkg: /home/anders/.ghc/x86_64-linux-6.12.1/package.conf.d/binary-shared-0.8-00180db675f2ea73ce16a4820071cd80.conf:
hGetContents: invalid argument (invalid UTF-8 byte sequence)

The author’s name, Jürgen Nicklisch-Franken, is written in UTF-8 in binary-shared.cabal. It is translated to Haskell \decimal-escaped Unicode syntax in package.conf.inplace, which is passed to ghc-pkg update. But the resulting .conf file contains the name in ISO-8859-1. This breaks ghc-pkg recache.

I’m using ghc6 6.12.1-13 on Ubuntu maverick amd64.