Comment 15 for bug 202974

Erich, your issue shows up only when upgrading from 3.2.0.0-1 to 3.2.0.0-1ubuntu0.1, installing version in hardy-proposed ex-novo is fine. Here's a workaround to help you upgrading to 3.2.0.0-1ubuntu0.1:

1) Open /var/lib/dpkg/info/libghc6-hgl-dev.prerm with your favourite editor (with root privileges)
2) Comment (or delete) this line: "/usr/lib/libghc6-hgl-dev/unregister.sh"
3) Save the file and exit from your editor
4) (Re)install libghc6-hgl-dev 3.2.0.0-1ubuntu0.1

Do you still notice the problem?