diff --git a/Python/ceval.c b/Python/ceval.c
index 9bc147b..ddfe3c4 100644
--- a/Python/ceval.c
+++ b/Python/ceval.c
@@ -272,6 +272,9 @@
 void
 PyEval_ReInitThreads(void)
 {
+	PyObject *threading, *result;
+	PyThreadState *tstate;
+
 	if (!interpreter_lock)
 		return;
 	/*XXX Can't use PyThread_free_lock here because it does too
@@ -281,6 +284,23 @@
 	interpreter_lock = PyThread_allocate_lock();
 	PyThread_acquire_lock(interpreter_lock, 1);
 	main_thread = PyThread_get_thread_ident();
+
+	/* Update the threading module with the new state.
+	 */
+	tstate = PyThreadState_GET();
+	threading = PyMapping_GetItemString(tstate->interp->modules,
+					    "threading");
+	if (threading == NULL) {
+		/* threading not imported */
+		PyErr_Clear();
+		return;
+	}
+	result = PyObject_CallMethod(threading, "_after_fork", NULL);
+	if (result == NULL)
+		PyErr_WriteUnraisable(threading);
+	else
+		Py_DECREF(result);
+	Py_DECREF(threading);
 }
 #endif