diff --git a/Modules/_tkinter.c b/Modules/_tkinter.c
index 566bf77..48916a5 100644
--- a/Modules/_tkinter.c
+++ b/Modules/_tkinter.c
@@ -1059,7 +1059,7 @@
 
 static PyTypeObject Tktt_Type =
 {
-  PyObject_HEAD_INIT (&PyType_Type)
+  PyObject_HEAD_INIT (NULL)
   0,				/*ob_size */
   "tktimertoken",		/*tp_name */
   sizeof (TkttObject),		/*tp_basicsize */
@@ -1240,7 +1240,7 @@
 
 static PyTypeObject Tkapp_Type =
 {
-  PyObject_HEAD_INIT (&PyType_Type)
+  PyObject_HEAD_INIT (NULL)
   0,				/*ob_size */
   "tkapp",			/*tp_name */
   sizeof (TkappObject),		/*tp_basicsize */
@@ -1335,6 +1335,9 @@
 #endif /* WITH_READLINE */
   PyObject *m, *d, *v;
 
+  Tkapp_Type.ob_type = &PyType_Type;
+  Tktt_Type.ob_type = &PyType_Type;
+
   m = Py_InitModule ("_tkinter", moduleMethods);
 
   d = PyModule_GetDict (m);