Index: Doc/library/_winreg.rst
===================================================================
--- Doc/library/_winreg.rst	(revision 76365)
+++ Doc/library/_winreg.rst	(working copy)
@@ -68,6 +68,29 @@
    :exc:`WindowsError` exception is  raised.
 
 
+.. function:: CreateKeyEx(key, sub_key[, res=0][, sam=KEY_ALL_ACCESS])
+
+   Creates or opens the specified key, returning a :dfn:`handle object`
+
+   *key* is an already open key, or one of the predefined  :const:`HKEY_\*`
+   constants.
+
+   *sub_key* is a string that names the key this method opens  or creates.
+
+   *res* is a reserved integer, and must be zero.  The default is zero.
+
+   *sam* is an integer that specifies an access mask that describes  the desired
+   security access for the key.  Default is :const:`KEY_ALL_ACCESS`
+
+   If *key* is one of the predefined keys, *sub_key* may  be ``None``. In that
+   case, the handle returned is the same key handle  passed in to the function.
+
+   If the key already exists, this function opens the existing key.
+
+   The return value is the handle of the opened key. If the function fails, a
+   :exc:`WindowsError` exception is  raised.
+
+
 .. function:: DeleteKey(key, sub_key)
 
    Deletes the specified key.
Index: Lib/test/test_winreg.py
===================================================================
--- Lib/test/test_winreg.py	(revision 76365)
+++ Lib/test/test_winreg.py	(working copy)
@@ -56,7 +56,7 @@
         CloseKey(hkey)
         DeleteKey(root, subkey)
 
-    def WriteTestData(self, root_key):
+    def WriteTestData(self, root_key, CreateKey=CreateKey):
         # Set the default value for this key.
         SetValue(root_key, test_key_name, REG_SZ, "Default value")
         key = CreateKey(root_key, test_key_name)
@@ -166,14 +166,17 @@
         except WindowsError: # Use this error name this time
             pass
 
-    def TestAll(self, root_key):
-        self.WriteTestData(root_key)
+    def TestAll(self, root_key, create_fn=CreateKey):
+        self.WriteTestData(root_key, create_fn)
         self.ReadTestData(root_key)
         self.DeleteTestData(root_key)
 
     def testLocalMachineRegistryWorks(self):
         self.TestAll(HKEY_CURRENT_USER)
 
+    def testLocalMachineRegistryWorksWithCreateKeyEx(self):
+        self.TestAll(HKEY_CURRENT_USER, CreateKeyEx)
+
     def testConnectRegistryToLocalMachineWorks(self):
         # perform minimal ConnectRegistry test which just invokes it
         h = ConnectRegistry(None, HKEY_LOCAL_MACHINE)
Index: PC/_winreg.c
===================================================================
--- PC/_winreg.c	(revision 76365)
+++ PC/_winreg.c	(working copy)
@@ -104,6 +104,21 @@
 "The return value is the handle of the opened key.\n"
 "If the function fails, an exception is raised.");
 
+PyDoc_STRVAR(CreateKeyEx_doc,
+"key = CreateKeyEx(key, sub_key, res, sam) - Creates or opens the specified key.\n"
+"\n"
+"key is an already open key, or one of the predefined HKEY_* constants\n"
+"sub_key is a string that names the key this method opens or creates.\n"
+"res is a reserved integer, and must be zero.  Default is zero.\n"
+"sam is an integer that specifies an access mask that describes the desired\n"
+" If key is one of the predefined keys, sub_key may be None. In that case,\n"
+" the handle returned is the same key handle passed in to the function.\n"
+"\n"
+"If the key already exists, this function opens the existing key\n"
+"\n"
+"The return value is the handle of the opened key.\n"
+"If the function fails, an exception is raised.");
+
 PyDoc_STRVAR(DeleteKey_doc,
 "DeleteKey(key, sub_key) - Deletes the specified key.\n"
 "\n"
@@ -1014,6 +1029,29 @@
 }
 
 static PyObject *
+PyCreateKeyEx(PyObject *self, PyObject *args)
+{
+	HKEY hKey;
+	PyObject *obKey;
+	char *subKey;
+	HKEY retKey;
+    int res = 0;
+    REGSAM sam = KEY_ALL_ACCESS;
+	long rc;
+	if (!PyArg_ParseTuple(args, "Oz|ii:CreateKeyEx", &obKey, &subKey,
+                          &res, &sam))
+		return NULL;
+	if (!PyHKEY_AsHKEY(obKey, &hKey, FALSE))
+		return NULL;
+
+    rc = RegCreateKeyEx(hKey, subKey, res, NULL, NULL, 
+                        sam, NULL, &retKey, NULL);
+	if (rc != ERROR_SUCCESS)
+		return PyErr_SetFromWindowsErrWithFunction(rc, "CreateKeyEx");
+	return PyHKEY_FromHKEY(retKey);
+}
+
+static PyObject *
 PyDeleteKey(PyObject *self, PyObject *args)
 {
 	HKEY hKey;
@@ -1576,6 +1614,7 @@
 	{"CloseKey",         PyCloseKey,        METH_VARARGS, CloseKey_doc},
 	{"ConnectRegistry",  PyConnectRegistry, METH_VARARGS, ConnectRegistry_doc},
 	{"CreateKey",        PyCreateKey,       METH_VARARGS, CreateKey_doc},
+    {"CreateKeyEx",      PyCreateKeyEx,     METH_VARARGS, CreateKeyEx_doc},
 	{"DeleteKey",        PyDeleteKey,       METH_VARARGS, DeleteKey_doc},
 	{"DeleteValue",      PyDeleteValue,     METH_VARARGS, DeleteValue_doc},
 	{"DisableReflectionKey", PyDisableReflectionKey, METH_VARARGS, DisableReflectionKey_doc},