Issue 2440: revert r62269 and r62279.  These changes were made in an effort to fix test_args2.Signed_TestCase.test_n(), which was failing on Windows x64 on the following line:  'self.failUnlessEqual(99, getargs_n(Long()))'.  Although the two commits *did* fix the test on Windows x64, it's become clear that it's the test that's incorrect, and the changes to PyNumber_Index() in particular were not warranted (and actually violate PEP 357).  This commit will get us back to where we were at r62268, before I started butchering things.
diff --git a/Objects/abstract.c b/Objects/abstract.c
index 684b0b4..dac80d9 100644
--- a/Objects/abstract.c
+++ b/Objects/abstract.c
@@ -1220,7 +1220,6 @@
 PyObject *
 PyNumber_Index(PyObject *item)
 {
-	PyNumberMethods *m;
 	PyObject *result = NULL;
 	if (item == NULL)
 		return null_error();
@@ -1228,9 +1227,8 @@
 		Py_INCREF(item);
 		return item;
 	}
-	m = item->ob_type->tp_as_number;
 	if (PyIndex_Check(item)) {
-		result = m->nb_index(item);
+		result = item->ob_type->tp_as_number->nb_index(item);
 		if (result && !PyLong_Check(result)) {
 			PyErr_Format(PyExc_TypeError,
 				     "__index__ returned non-int "
@@ -1240,17 +1238,7 @@
 			return NULL;
 		}
 	}
-	else if (m && m->nb_int != NULL && m->nb_float == NULL) {
-		result = m->nb_int(item);
-		if (result && !PyLong_Check(result)) {
-			PyErr_Format(PyExc_TypeError,
-				     "__int__ returned non-int "
-				     "(type %.200s)",
-				     result->ob_type->tp_name);
-			Py_DECREF(result);
-			return NULL;
-		}
-	} else {
+	else {
 		PyErr_Format(PyExc_TypeError,
 			     "'%.200s' object cannot be interpreted "
 			     "as an integer", item->ob_type->tp_name);