This got fixed for classic classes in r60057,

and backported to 2.5.2 in 60056.

Lib/test/crashers/weakref_in_del.py

@@ -1,17 +0,0 @@
-import weakref
-
-# http://python.org/sf/1377858
-# Fixed for new-style classes in 2.5c1.
-
-ref = None
-
-def test_weakref_in_del():
-    class Target():
-        def __del__(self):
-            global ref
-            ref = weakref.ref(self)
-
-    w = Target()
-
-if __name__ == '__main__':
-    test_weakref_in_del()