diff --git a/pkgs/os-specific/linux/kernel/linux-2.6.31-rc4.nix b/pkgs/os-specific/linux/kernel/linux-2.6.31-rc4.nix
new file mode 100644
index 000000000000..726682b9696a
--- /dev/null
+++ b/pkgs/os-specific/linux/kernel/linux-2.6.31-rc4.nix
@@ -0,0 +1,31 @@
+args @ {stdenv, fetchurl, userModeLinux ? false, oldI686 ? false, ...}:
+
+assert !userModeLinux;
+
+import ./generic.nix (
+
+  let
+    baseVersion = "2.6.30"; 
+  in
+
+  rec {
+    version = "2.6.31-rc4";
+  
+    src = fetchurl {
+      url = "mirror://kernel/linux/kernel/v2.6/linux-${baseVersion}.tar.bz2";
+      sha256 = "d7b9f19b92fd5c693c16cd62f441d051b699f28ec6a175d1b464e58bacd8c78f";
+    };
+
+    features = {
+      iwlwifi = true;
+    };
+ 
+    config =
+      if stdenv.system == "i686-linux" then if oldI686 then ./config-2.6.31-rc3-all-mod-i686-older else 
+        ./config-2.6.31-rc3-all-mod-i686 else
+      if stdenv.system == "x86_64-linux" then ./config-2.6.31-rc3-all-mod-amd64 else
+      abort "No kernel configuration for your platform!";
+  }
+
+  // args
+)
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index c01a4b11a8ac..f4d4a9a10cde 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -5058,6 +5058,23 @@ let
     ];
   };
 
+  kernel_2_6_31_rc4 = makeOverridable (import ../os-specific/linux/kernel/linux-2.6.31-rc4.nix) {
+    inherit fetchurl stdenv perl mktemp module_init_tools;
+    kernelPatches = [ 
+      { name = "rc4 patch";
+        patch = fetchurl {
+          url =  "http://kernel.org/pub/linux/kernel/v2.6/testing/patch-2.6.31-rc4.bz2";
+          sha256 =  "1qyjh8gf0clj4a8aiblrn2p7244h7dp2psnidylxr2y53z2vg62s";
+	};
+      }
+    ];
+  };
+
+  # For older x86 processors without PAE/PAT
+  kernel_2_6_31_rc4_old_i686 = kernel_2_6_31_rc4.override {
+    oldI686 = true;
+  };
+
   kernel_2_6_31_rc3 = makeOverridable (import ../os-specific/linux/kernel/linux-2.6.31-rc3.nix) {
     inherit fetchurl stdenv perl mktemp module_init_tools;
     kernelPatches = [ 
@@ -5197,6 +5214,8 @@ let
   kernelPackages_2_6_27 = recurseIntoAttrs (kernelPackagesFor kernel_2_6_27);
   kernelPackages_2_6_28 = recurseIntoAttrs (kernelPackagesFor kernel_2_6_28);
   kernelPackages_2_6_29 = recurseIntoAttrs (kernelPackagesFor kernel_2_6_29);
+  kernelPackages_2_6_31_rc4 =          recurseIntoAttrs (kernelPackagesFor kernel_2_6_31_rc4);
+  kernelPackages_2_6_31_rc4_old_i686 = recurseIntoAttrs (kernelPackagesFor kernel_2_6_31_rc4_old_i686);
   kernelPackages_2_6_31_rc3 = recurseIntoAttrs (kernelPackagesFor kernel_2_6_31_rc3);
   kernelPackages_2_6_31_rc3_old_i686 = recurseIntoAttrs (kernelPackagesFor kernel_2_6_31_rc3_old_i686);
   kernelPackages_2_6_31_rc2 = recurseIntoAttrs (kernelPackagesFor kernel_2_6_31_rc2);
diff --git a/pkgs/top-level/release.nix b/pkgs/top-level/release.nix
index bb93a765caa1..8f18a79cbc44 100644
--- a/pkgs/top-level/release.nix
+++ b/pkgs/top-level/release.nix
@@ -499,12 +499,12 @@ in {
     virtualbox = linux;
   };
 
-  kernelPackages_2_6_31_rc3 = {
+  kernelPackages_2_6_31_rc4 = {
     aufs = linux;
     kernel = linux;
   };
 
-  kernelPackages_2_6_31_rc3_old_i686 = {
+  kernelPackages_2_6_31_rc4_old_i686 = {
     aufs = ["i686-linux"];
     kernel = ["i686-linux"];
   };