Index: Python/bltinmodule.c
===================================================================
--- Python/bltinmodule.c	(revision 80673)
+++ Python/bltinmodule.c	(working copy)
@@ -1746,6 +1746,39 @@
 	return -1;
 }
 
+static PyObject *
+get_range_argument(PyObject *arg, const char *name)
+{
+	PyObject *v;
+	PyNumberMethods *nb;
+	if (PyInt_Check(arg) || PyLong_Check(arg))
+		return arg;
+	
+	if (PyFloat_Check(arg) ||
+	    (nb = Py_TYPE(arg)->tp_as_number) == NULL ||
+            nb->nb_int == NULL) {
+		Py_DECREF(arg);
+		PyErr_Format(PyExc_TypeError,
+			     "range() integer %s argument expected, got %s.",
+			     name, arg->ob_type->tp_name);
+		return NULL;
+	}
+
+	v = nb->nb_int(arg);
+	Py_DECREF(arg);
+
+	if (v == NULL)
+		return NULL;
+	
+	if (PyInt_Check(v) || PyLong_Check(v))
+		return v;
+	
+	Py_DECREF(v);
+	PyErr_SetString(PyExc_TypeError,
+			"nb_int should return int object");
+	return NULL;
+}
+ 
 /* An extension of builtin_range() that handles the case when PyLong
  * arguments are given. */
 static PyObject *
@@ -1799,29 +1832,18 @@
 		Py_INCREF(istep);
 	}
 
-	if (!PyInt_Check(ilow) && !PyLong_Check(ilow)) {
-		PyErr_Format(PyExc_TypeError,
-			     "range() integer start argument expected, got %s.",
-			     ilow->ob_type->tp_name);
+	if (!(ilow = get_range_argument(ilow, "start")))
 		goto Fail;
-	}
 
-	if (!PyInt_Check(ihigh) && !PyLong_Check(ihigh)) {
-		PyErr_Format(PyExc_TypeError,
-			     "range() integer end argument expected, got %s.",
-			     ihigh->ob_type->tp_name);
+	if (!(ihigh = get_range_argument(ihigh, "end")))
 		goto Fail;
-	}
 
-	if (!PyInt_Check(istep) && !PyLong_Check(istep)) {
-		PyErr_Format(PyExc_TypeError,
-			     "range() integer step argument expected, got %s.",
-			     istep->ob_type->tp_name);
+	if (!(istep = get_range_argument(istep, "step")))
 		goto Fail;
-	}
 
 	if (PyObject_Cmp(istep, zero, &cmp_result) == -1)
 		goto Fail;
+
 	if (cmp_result == 0) {
 		PyErr_SetString(PyExc_ValueError,
 				"range() step argument must not be zero");
@@ -1875,8 +1897,8 @@
 	return v;
 
   Fail:
-	Py_DECREF(ilow);
-	Py_DECREF(ihigh);
+	Py_XDECREF(ilow);
+	Py_XDECREF(ihigh);
 	Py_XDECREF(istep);
 	Py_DECREF(zero);
 	Py_XDECREF(curnum);
Index: Lib/test/test_builtin.py
===================================================================
--- Lib/test/test_builtin.py	(revision 80673)
+++ Lib/test/test_builtin.py	(working copy)
@@ -1080,6 +1080,36 @@
         self.assertRaises(OverflowError, range, -sys.maxint, sys.maxint)
         self.assertRaises(OverflowError, range, 0, 2*sys.maxint)
 
+        bignum = 2*sys.maxint
+        # Old-style user-defined class with __int__ method
+        class I0:
+            def __init__(self, n):
+                self.n = int(n)
+            def __int__(self):
+                return self.n
+        self.assertEqual(range(I0(bignum), I0(bignum + 1)), [bignum])
+
+        # New-style user-defined class with __int__ method
+        class I1(object):
+            def __init__(self, n):
+                self.n = int(n)
+            def __int__(self):
+                return self.n
+        self.assertEqual(range(I1(bignum), I1(bignum + 1)), [bignum])
+
+        # New-style user-defined class with failing __int__ method
+        class IX(object):
+            def __int__(self):
+                raise RuntimeError
+        self.assertRaises(RuntimeError, range, IX())
+
+        # New-style user-defined class with invalid __int__ method
+        class IN(object):
+            def __int__(self):
+                return "not a number"
+        self.assertRaises(TypeError, range, IN())
+
+
     def test_input_and_raw_input(self):
         self.write_testfile()
         fp = open(TESTFN, 'r')