anchor.diff:              # installing new applications to update the cache.
               # See http://lists-archives.org/kde-devel/26175-what-when-will-icon-cache-refresh.html
               rm -fv $HOME/.kde/cache-*/icon-cache.kcache
  +
  +            # Qt writes a weird ‘libraryPath’ line to
  +            # ~/.config/Trolltech.conf that causes the KDE plugin
  +            # paths of previous KDE invocations to be searched.
  +            # Obviously using mismatching KDE libraries is potentially
  +            # disastrous, so here we nuke references to the Nix store
  +            # in Trolltech.conf.  A better solution would be to stop
  +            # Qt from doing this wackiness in the first place.
  +            if [ -e $HOME/.config/Trolltech.conf ]; then
  +                sed -e '/nix\\store\|nix\/store/ d' -i $HOME/.config/Trolltech.conf
  +            fi
   
               # Start KDE.
               exec ${pkgs.kde4.kdebase_workspace}/bin/startkde
  
positive.code:           pkgs.shared_mime_info
            xorg.xmessage # so that startkde can show error messages
            xorg.xset # used by startkde, non-essential
          ]
        ) ++ config.environment.kdePackages;
  
  
negative.code: 
      environment.kdePackages = mkOption {
        default = [];
        example = "[ pkgs.kde4.kdesdk ]";
        type = types.list types.package;
        description = "This option is obsolete.  Please use <option>environment.systemPackages</option> instead.";
      };
  