After using emacs customize to add '(haskell-mode-hook (quote (turn-on-haskell-indentation))) to the .emacs file and closing all haskell buffers, rebooting emacs and opening a haskell file again, I no longer have this problem.
It would probably be a sensible default to have some haskell-mode-hook configured right after installing haskell-mode.
After using emacs customize to add '(haskell-mode-hook (quote (turn-on- haskell- indentation) )) to the .emacs file and closing all haskell buffers, rebooting emacs and opening a haskell file again, I no longer have this problem.
It would probably be a sensible default to have some haskell-mode-hook configured right after installing haskell-mode.
Hope this helps others, too!