diff --git a/pkgs/applications/networking/browsers/firefox/default.nix b/pkgs/applications/networking/browsers/firefox/default.nix
index 606a96d388d6..ddab35093629 100644
--- a/pkgs/applications/networking/browsers/firefox/default.nix
+++ b/pkgs/applications/networking/browsers/firefox/default.nix
@@ -22,7 +22,13 @@ stdenv.mkDerivation {
     pkgconfig gtk perl zip libIDL libXi libjpeg libpng zlib cairo
   ];
 
-  patches = [./writable-copies.patch];
+  patches = [
+    ./writable-copies.patch
+    # Ugh, inexplicable problem since GTK+ 2.10.  Probably a Firefox
+    # bug, but I don't know.  See
+    # http://lists.gobolinux.org/pipermail/gobolinux-users/2007-January/004344.html
+    ./xlibs.patch
+  ];
 
   configureFlags = [
     "--enable-application=browser"
diff --git a/pkgs/applications/networking/browsers/firefox/xlibs.patch b/pkgs/applications/networking/browsers/firefox/xlibs.patch
new file mode 100644
index 000000000000..a656fbf9beb4
--- /dev/null
+++ b/pkgs/applications/networking/browsers/firefox/xlibs.patch
@@ -0,0 +1,10 @@
+--- mozilla/layout/build/Makefile.in.orig	2007-01-13 14:23:19.000000000 -0200
++++ mozilla/layout/build/Makefile.in	2007-01-13 14:24:55.000000000 -0200
+@@ -282,5 +282,6 @@ LDFLAGS += -Wl,-LD_LAYOUT:lgot_buffer=50
+ endif
+ endif
+ 
++LDFLAGS += -lX11 -lXrender
+ 
+ export:: $(BUILD_DATE)
+ 
\ No newline at end of file
diff --git a/pkgs/applications/networking/browsers/mozilla-plugins/mplayerplug-in/default.nix b/pkgs/applications/networking/browsers/mozilla-plugins/mplayerplug-in/default.nix
index 79302d28127e..92dabe96a532 100644
--- a/pkgs/applications/networking/browsers/mozilla-plugins/mplayerplug-in/default.nix
+++ b/pkgs/applications/networking/browsers/mozilla-plugins/mplayerplug-in/default.nix
@@ -1,19 +1,19 @@
-{stdenv, fetchurl, pkgconfig, firefox, libXpm}:
+{stdenv, fetchurl, pkgconfig, firefox, libXpm, gettext}:
 
 # Note: we shouldn't be dependent on Firefox.  The only thing we need
 # are the include files so that we can access the plugin API (I
 # think).
 
 (stdenv.mkDerivation {
-  name = "mplayerplug-in-3.31";
+  name = "mplayerplug-in-3.35";
 
   builder = ./builder.sh;
   src = fetchurl {
-    url = http://nix.cs.uu.nl/dist/tarballs/mplayerplug-in-3.31.tar.gz;
-    md5 = "be26b17cde385c7a34fc634d2c88c5c9";
+    url = http://heanet.dl.sourceforge.net/sourceforge/mplayerplug-in/mplayerplug-in-3.35.tar.gz;
+    sha256 = "0zxd2nnmj4n9rkndd614ljv7ylz4f4jqvx1wswqfw5j7hwxm34dw";
   };
 
-  buildInputs = [pkgconfig firefox (firefox.gtk) libXpm];
+  buildInputs = [pkgconfig firefox (firefox.gtk) libXpm gettext];
   
   inherit firefox;
 }) // {mozillaPlugin = "/lib/mozilla/plugins";}
diff --git a/pkgs/development/tools/misc/pkgconfig/pkgconfig-0.21.nix b/pkgs/development/tools/misc/pkgconfig/pkgconfig-0.21.nix
index b50ccc6b6401..520def967f47 100644
--- a/pkgs/development/tools/misc/pkgconfig/pkgconfig-0.21.nix
+++ b/pkgs/development/tools/misc/pkgconfig/pkgconfig-0.21.nix
@@ -8,4 +8,13 @@ stdenv.mkDerivation {
     url = http://nix.cs.uu.nl/dist/tarballs/pkg-config-0.21.tar.gz;
     md5 = "476f45fab1504aac6697aa7785f0ab91";
   };
+
+  patches = [
+    # Process Requires.private properly, see
+    # http://bugs.freedesktop.org/show_bug.cgi?id=4738.
+    (fetchurl {
+      url = http://bugs.freedesktop.org/attachment.cgi?id=8494;
+      sha256 = "1pcrdbb7dypg2biy0yqc7bdxak5zii8agqljdvk7j4wbyghpqzws";
+    })
+  ];
 }
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index b9c267790c80..e77975ab022d 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -1118,11 +1118,13 @@ rec {
    * pkgconfig is optionally taken from the stdenv to allow bootstrapping
    * of glib and pkgconfig itself on MinGW.
    */
-  pkgconfig = useFromStdenv (stdenv ? pkgconfig) stdenv.pkgconfig
+  pkgconfigOld = useFromStdenv (stdenv ? pkgconfig) stdenv.pkgconfig
     (import ../development/tools/misc/pkgconfig {
       inherit fetchurl stdenv;
     });
 
+  pkgconfig = pkgconfig_latest;
+
   pkgconfig017x = import ../development/tools/misc/pkgconfig/pkgconfig-0.17.2.nix {
     inherit fetchurl stdenv;
   };
@@ -2732,7 +2734,7 @@ rec {
   };
 
   MPlayerPlugin = import ../applications/networking/browsers/mozilla-plugins/mplayerplug-in {
-    inherit fetchurl stdenv pkgconfig firefox;
+    inherit fetchurl stdenv pkgconfig firefox gettext;
     inherit (xlibs) libXpm;
     # !!! should depend on MPlayer
   };