diff --git a/etc/bashrc.sh b/etc/bashrc.sh
index 4ec3b4ab415..baaed726ee1 100644
--- a/etc/bashrc.sh
+++ b/etc/bashrc.sh
@@ -15,6 +15,9 @@ export LANG=@defaultLocale@
 export EDITOR=nano
 export INFOPATH=/var/run/current-system/sw/info:/var/run/current-system/sw/share/info
 export LOCATE_PATH=/var/cache/locatedb
+export KDEDIRS=/var/run/current-system/sw
+export XDG_CONFIG_DIRS=/var/run/current-system/sw/etc/xdg
+export XDG_DATA_DIRS=/var/run/current-system/sw/share
 
 
 # Set up secure multi-user builds: non-root users build through the
@@ -41,7 +44,7 @@ for i in $NIX_PROFILES; do # !!! reverse
     export PKG_CONFIG_PATH="$i/lib/pkgconfig:$PKG_CONFIG_PATH"
 
     # Automake's `aclocal' bails out if it finds non-existent directories
-    # in its path.
+    # in its path.  !!! We should fix aclocal instead.
     if [ -d "$i/share/aclocal" ]
     then
 	export ACLOCAL_PATH="$i/share/aclocal:$ACLOCAL_PATH"
@@ -50,6 +53,11 @@ for i in $NIX_PROFILES; do # !!! reverse
 
     # GStreamer.
     export GST_PLUGIN_PATH="$i/lib/gstreamer-0.10:$GST_PLUGIN_PATH"
+
+    # KDE/Gnome stuff.
+    export KDEDIRS=$i:$KDEDIRS
+    export XDG_CONFIG_DIRS=$i/etc/xdg:$XDG_CONFIG_DIRS
+    export XDG_DATA_DIRS=$i/share:$XDG_DATA_DIRS
 done
 
 
diff --git a/system/options.nix b/system/options.nix
index 2a6498ed80a..a2952b4a325 100644
--- a/system/options.nix
+++ b/system/options.nix
@@ -2959,7 +2959,7 @@ root        ALL=(ALL) SETENV: ALL
   environment = {
 
     pathsToLink = mkOption {
-      default = ["/bin" "/sbin" "/lib" "/share" "/man" "/info"];
+      default = ["/bin" "/sbin" "/lib" "/share" "/man" "/info" "/etc"];
       example = ["/"];
       description = "
         Lists directories to be symlinked in `/var/run/current-system/sw'.
diff --git a/system/system.nix b/system/system.nix
index 7d814993844..913913db9af 100644
--- a/system/system.nix
+++ b/system/system.nix
@@ -266,6 +266,15 @@ rec {
     inherit (config.environment) pathsToLink;
 
     ignoreCollisions = true;
+
+    postBuild =
+      if config.services.xserver.sessionType == "kde4" then
+        # Rebuild the MIME database.  Otherwise KDE won't be able to
+        # find many MIME types.
+        ''
+          ${pkgs.shared_mime_info}/bin/update-mime-database $out/share/mime
+        ''
+      else "";
   };
 
 
@@ -301,10 +310,10 @@ rec {
     inherit (usersGroups) createUsersGroups usersList groupsList;
 
     path = [
-        pkgs.coreutils pkgs.gnugrep pkgs.findutils
-        pkgs.glibc # needed for getent
-        pkgs.pwdutils
-      ];
+      pkgs.coreutils pkgs.gnugrep pkgs.findutils
+      pkgs.glibc # needed for getent
+      pkgs.pwdutils
+    ];
 
     adjustSetuidOwner = pkgs.lib.concatStrings (map 
       (_entry: let entry = {
diff --git a/upstart-jobs/xserver.nix b/upstart-jobs/xserver.nix
index a2961137d9d..c889c6427a9 100644
--- a/upstart-jobs/xserver.nix
+++ b/upstart-jobs/xserver.nix
@@ -296,9 +296,6 @@ let
     '' else if sessionType == "kde4" then ''
 
       # Start KDE.
-      export KDEDIRS=$HOME/.nix-profile:/nix/var/nix/profiles/default:${pkgs.kde42.kdelibs}:${pkgs.kde42.kdebase}:${pkgs.kde42.kdebase_runtime}:${pkgs.kde42.kdebase_workspace}
-      export XDG_CONFIG_DIRS=${pkgs.kde42.kdelibs}/etc/xdg:${pkgs.kde42.kdebase_runtime}/etc/xdg:${pkgs.kde42.kdebase_workspace}/etc/xdg
-      export XDG_DATA_DIRS=${pkgs.kde42.kdelibs}/share:${pkgs.kde42.kdebase}/share:${pkgs.kde42.kdebase_runtime}/share:${pkgs.kde42.kdebase_workspace}/share:${pkgs.shared_mime_info}/share
       exec ${pkgs.kde42.kdebase_workspace}/bin/startkde
 
     '' else ''
@@ -398,6 +395,8 @@ rec {
     pkgs.kde42.kdebase
     pkgs.kde42.kdebase_runtime
     pkgs.kde42.kdebase_workspace
+    pkgs.kde42.kdegames
+    pkgs.shared_mime_info
     xorg.xset # used by startkde, non-essential
   ]
   ++ optional (videoDriver == "nvidia") [