diff --git a/etc/bashrc.sh b/etc/bashrc.sh
index 4ec3b4ab4158..20b78b21c632 100644
--- a/etc/bashrc.sh
+++ b/etc/bashrc.sh
@@ -15,7 +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
 # Nix daemon.
@@ -41,7 +43,7 @@ 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 +52,11 @@ 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 babd4cfc1622..34ae64a3c51b 100644
--- a/system/options.nix
+++ b/system/options.nix
@@ -2127,7 +2127,7 @@ in
   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-options.nix b/system/system-options.nix
index b1688cdda805..fdbd57a79f04 100644
--- a/system/system-options.nix
+++ b/system/system-options.nix
@@ -64,6 +64,16 @@ let
           inherit (config.environment) pathsToLink;
 
           ignoreCollisions = true;
+
+          # TODO: move this to upstart-jobs/xserver/desktopManager/kde4.nix
+          postBuild =
+            if config.services.xserver.desktopManager.kde4.enable 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 "";
         };
       };
 
diff --git a/upstart-jobs/xserver/desktopManager/kde4.nix b/upstart-jobs/xserver/desktopManager/kde4.nix
index 2694057720be..d7d91812a5da 100644
--- a/upstart-jobs/xserver/desktopManager/kde4.nix
+++ b/upstart-jobs/xserver/desktopManager/kde4.nix
@@ -29,9 +29,6 @@ mkIf cfg.enable {
           name = "kde4";
           start = ''
             # 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
           '';
         }];
@@ -54,6 +51,8 @@ mkIf cfg.enable {
       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
     ];