diff --git a/pkgs/applications/virtualization/xen/default.nix b/pkgs/applications/virtualization/xen/default.nix
index 46625436798..b7c9c1c3d5b 100644
--- a/pkgs/applications/virtualization/xen/default.nix
+++ b/pkgs/applications/virtualization/xen/default.nix
@@ -1,36 +1,39 @@
-args :  
-let 
-  lib = args.lib;
-  fetchurl = args.fetchurl;
-  fullDepEntry = args.fullDepEntry;
+{ stdenv, fetchurl, which, zlib, pkgconfig, SDL, openssl, python
+, libuuid, gettext, ncurses, dev86, iasl, pciutils, bzip2, xz }:
+
+let version = "4.0.1"; in 
+
+stdenv.mkDerivation {
+  name = "xen-${version}";
 
-  version = lib.attrByPath ["version"] "3.3.0" args; 
-  _buildInputs = with args; [
-    python e2fsprogs gnutls pkgconfig libjpeg 
-    ncurses SDL libvncserver zlib graphviz ghostscript 
-    texLive
-  ];
-in
-rec {
   src = fetchurl {
     url = "http://bits.xensource.com/oss-xen/release/${version}/xen-${version}.tar.gz";
-    sha256 = "0vghm31pqq8sc6x81jass2h5s22jlvv582xb8aq4j4cbcc5qixc9";
+    sha256 = "0ww8j5fa2jxg0zyx7d7z9jyv2j47m8w420sy16w3rf8d80lisvbf";
   };
 
-  buildInputs = lib.filter (x: x != null) _buildInputs;
-  configureFlags = [];
+  patches =
+    [ # Xen looks for headers in /usr/include and for libraries using
+      # ldconfig.  Don't do that.
+      ./has-header.patch
+    ];
 
-  /* doConfigure should be specified separately */
-  phaseNames = ["makeTools" "makeXen"];
+  buildInputs =
+    [ which zlib pkgconfig SDL openssl python libuuid gettext ncurses
+      dev86 iasl pciutils bzip2 xz
+    ];
+
+  makeFlags = "PREFIX=$(out)";
+
+  buildFlags = "xen tools";
+
+  installPhase =
+    ''
+      cp -prvd dist/install/nix/store/* $out
+      cp -prvd dist/install/boot $out/boot
+    ''; # */
 
-  makeTools = fullDepEntry (''make -C tools install PREFIX=$out '') 
-    ["minInit" "addInputs" "doUnpack"];
-      
-  makeXen = fullDepEntry (''make -C xen install PREFIX=$out '') 
-    ["minInit" "addInputs" "doUnpack"];
-      
-  name = "xen-" + version;
   meta = {
-    description = "Xen paravirtualization tools";
+    homepage = http://www.xen.org/;
+    description = "Xen hypervisor and management tools for Dom0";
   };
 }
diff --git a/pkgs/applications/virtualization/xen/has-header.patch b/pkgs/applications/virtualization/xen/has-header.patch
new file mode 100644
index 00000000000..b59dd7ea5af
--- /dev/null
+++ b/pkgs/applications/virtualization/xen/has-header.patch
@@ -0,0 +1,40 @@
+diff -ru --exclude '*~' xen-4.0.1-orig/tools/check/funcs.sh xen-4.0.1/tools/check/funcs.sh
+--- xen-4.0.1-orig/tools/check/funcs.sh	2010-08-25 12:22:07.000000000 +0200
++++ xen-4.0.1/tools/check/funcs.sh	2010-09-09 17:47:20.000000000 +0200
+@@ -25,33 +25,13 @@
+ }
+ 
+ has_header() {
+-	case $1 in
+-		/*) ;;
+-		*) set -- "/usr/include/$1" ;;
+-	esac
+-
+-	check_sys_root || return 1
+-
+-	test -r "$CROSS_SYS_ROOT$1"
+-	return $?
++	echo "#include <$1>" | gcc -E - > /dev/null && return 0
++	return 1
+ }
+ 
+ has_lib() {
+ 	check_sys_root || return 1
+-
+-	# subshell to prevent pollution of caller's environment
+-	(
+-	PATH=/sbin:$PATH        # for ldconfig
+-
+-	# This relatively common in a sys-root; libs are installed but
+-	# ldconfig hasn't run there, so ldconfig -p won't work.
+-	if [ "$OS" = Linux -a ! -f "$CROSS_SYS_ROOT/etc/ld.so.cache" ]; then
+-	    echo "Please run ldconfig -r \"$CROSS_SYS_ROOT\" to generate ld.so.cache"
+-	    # fall through; ldconfig test below should fail
+-	fi
+-	ldconfig -p ${CROSS_SYS_ROOT+-r "$CROSS_SYS_ROOT"} | grep -Fq "$1"
+-	return $?
+-	)
++	return 0
+ }
+ 
+ test_link() {
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index ead85f07f0d..1c57f9b84f4 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -6314,15 +6314,7 @@ let
 
   xdg_utils = callPackage ../tools/X11/xdg-utils { };
 
-  /* Doesn't work yet
-
-  xen = builderDefsPackage (import ../applications/virtualization/xen) {
-    inherit python e2fsprogs gnutls pkgconfig libjpeg
-      ncurses SDL libvncserver zlib;
-    texLive = if (getConfig ["xen" "texLive"] false) then texLive else null;
-    graphviz = if (getConfig ["xen" "graphviz"] false) then graphviz else null;
-    ghostscript = if (getConfig ["xen" "ghostscript"] false) then ghostscript else null;
-  }; */
+  xen = callPackage ../applications/virtualization/xen { };
 
   xfig = callPackage ../applications/graphics/xfig {
     stdenv = overrideGCC stdenv gcc34;