diff --git a/pkgs/applications/networking/browsers/firefox/4.0.nix b/pkgs/applications/networking/browsers/firefox/4.0.nix
index 96fe1f91cf5b..5ca685ab3727 100644
--- a/pkgs/applications/networking/browsers/firefox/4.0.nix
+++ b/pkgs/applications/networking/browsers/firefox/4.0.nix
@@ -1,7 +1,7 @@
 { stdenv, fetchurl, pkgconfig, gtk, pango, perl, python, zip, libIDL
 , libjpeg, libpng, zlib, cairo, dbus, dbus_glib, bzip2, xlibs
 , freetype, fontconfig, file, alsaLib, nspr, nss, libnotify
-, libvpx, yasm, mesa, wirelesstools
+, libvpx, yasm, mesa
 
 , # If you want the resulting program to call itself "Firefox" instead
   # of "Shiretoko" or whatever, enable this option.  However, those
@@ -25,6 +25,7 @@ rec {
     sha1 = "403da9dd65662e5c4dd34299214e04cb6f80575e";
   };
 
+  
   commonConfigureFlags =
     [ "--enable-optimize"
       "--disable-debug"
@@ -33,13 +34,17 @@ rec {
       "--with-system-zlib"
       "--with-system-bz2"
       "--with-system-nspr"
-      #"--with-system-nss"
+      # "--with-system-nss"
       # "--with-system-png" # <-- "--with-system-png won't work because the system's libpng doesn't have APNG support"
       "--enable-system-cairo"
-      #"--enable-system-sqlite" # <-- this seems to be discouraged
+      # Compiling with the Nixpkgs SQLite gives:
+      # "configure: error: System SQLite library is not compiled with SQLITE_SECURE_DELETE."
+      # "--enable-system-sqlite"
       "--disable-crashreporter"
       "--disable-tests"
       "--disable-necko-wifi" # maybe we want to enable this at some point
+      "--disable-installer" 
+      "--disable-updater"
     ];
 
 
@@ -53,7 +58,7 @@ rec {
         python dbus dbus_glib pango freetype fontconfig xlibs.libXi
         xlibs.libX11 xlibs.libXrender xlibs.libXft xlibs.libXt file
         alsaLib nspr /* nss */ libnotify xlibs.pixman libvpx yasm mesa
-	wirelesstools xlibs.libXScrnSaver xlibs.scrnsaverproto
+	xlibs.libXScrnSaver xlibs.scrnsaverproto
 	xlibs.libXext xlibs.xextproto
       ];
 
@@ -64,18 +69,20 @@ rec {
 
     enableParallelBuilding = true;
       
-    # !!! Temporary hack.
-    preBuild = ''
-      export NIX_ENFORCE_PURITY=
-    '';
-
     # Hack to work around make's idea of -lbz2 dependency
-    preConfigure = ''
-     find . -name Makefile.in -execdir sed -i '{}' -e '1ivpath %.so ${
-       stdenv.lib.concatStringsSep ":" 
-         (map (s : s + "/lib") (buildInputs ++ [stdenv.gcc.libc]))
-     }' ';'
-    '';
+    preConfigure =
+      ''
+        find . -name Makefile.in -execdir sed -i '{}' -e '1ivpath %.so ${
+          stdenv.lib.concatStringsSep ":" 
+            (map (s : s + "/lib") (buildInputs ++ [stdenv.gcc.libc]))
+        }' ';'
+      '';
+
+    # !!! Temporary hack.
+    preBuild =
+      ''
+        export NIX_ENFORCE_PURITY=
+      '';
 
     installFlags = "SKIP_GRE_REGISTRATION=1";
 
@@ -120,7 +127,7 @@ rec {
     buildInputs =
       [ pkgconfig gtk perl zip libIDL libjpeg zlib cairo bzip2 python
         dbus dbus_glib pango freetype fontconfig alsaLib nspr libnotify
-        xlibs.pixman libvpx yasm mesa wirelesstools
+        xlibs.pixman libvpx yasm mesa
       ];
 
     propagatedBuildInputs = [xulrunner];
@@ -133,24 +140,19 @@ rec {
       ++ commonConfigureFlags
       ++ stdenv.lib.optional enableOfficialBranding "--enable-official-branding";
 
-    postInstall = ''
-      libDir=$(cd $out/lib && ls -d firefox-[0-9]*)
-      test -n "$libDir"
-
-      ln -s ${xulrunner}/lib/xulrunner-${xulrunner.version} $out/lib/$libDir/xulrunner
-
-      # Register extensions etc. !!! is this needed anymore?
-      echo "running firefox -register..."
-      $out/bin/firefox -register
-    ''; # */
-
     # Hack to work around make's idea of -lbz2 dependency
-    preConfigure = ''
-     find . -name Makefile.in -execdir sed -i '{}' -e '1ivpath %.so ${
-       stdenv.lib.concatStringsSep ":" 
-         (map (s : s + "/lib") (buildInputs ++ [stdenv.gcc.libc]))
-     }' ';'
-    '';
+    preConfigure =
+      ''
+        find . -name Makefile.in -execdir sed -i '{}' -e '1ivpath %.so ${
+          stdenv.lib.concatStringsSep ":" 
+            (map (s : s + "/lib") (buildInputs ++ [stdenv.gcc.libc]))
+        }' ';'
+      '';
+
+    postInstall =
+      ''
+        ln -s ${xulrunner}/lib/xulrunner-${xulrunner.version} $(echo $out/lib/firefox-*)/xulrunner
+      ''; # */
 
     meta = {
       description = "Mozilla Firefox - the browser, reloaded";