diff -r 6b2f703a38c2 Lib/test/test_threading.py
--- a/Lib/test/test_threading.py	Sun Jan 20 15:50:05 2008 +0100
+++ b/Lib/test/test_threading.py	Tue Jan 22 01:11:14 2008 +0100
@@ -236,6 +236,24 @@ class ThreadTests(unittest.TestCase):
             """])
         self.assertEqual(rc, 42)
 
+    def test_enumerate_after_join(self):
+        # Try hard to trigger #1703448: a thread is still returned in
+        # threading.enumerate() after it has been join()ed.
+        enum = threading.enumerate
+        old_interval = sys.getcheckinterval()
+        sys.setcheckinterval(1)
+        try:
+            for i in xrange(1, 1000):
+                t = threading.Thread(target=lambda: None)
+                t.start()
+                t.join()
+                l = enum()
+                self.assertFalse(t in l,
+                    "#1703448 triggered after %d trials: %s" % (i, l))
+        finally:
+            sys.setcheckinterval(old_interval)
+
+
 class ThreadingExceptionTests(unittest.TestCase):
     # A RuntimeError should be raised if Thread.start() is called
     # multiple times.
diff -r 6b2f703a38c2 Lib/threading.py
--- a/Lib/threading.py	Sun Jan 20 15:50:05 2008 +0100
+++ b/Lib/threading.py	Tue Jan 22 01:11:14 2008 +0100
@@ -524,11 +524,12 @@ class Thread(_Verbose):
                 if __debug__:
                     self._note("%s.__bootstrap(): normal return", self)
         finally:
-            self.__stop()
-            try:
-                self.__delete()
-            except:
-                pass
+            with _active_limbo_lock:
+                self.__stop()
+                try:
+                    del _active[_get_ident()]
+                except:
+                    pass
 
     def __stop(self):
         self.__block.acquire()