diff -r 76c5f3371db6 Lib/test/test_int.py
--- a/Lib/test/test_int.py	Sun Dec 23 15:35:23 2012 -0800
+++ b/Lib/test/test_int.py	Mon Dec 24 11:41:33 2012 +0200
@@ -230,15 +230,9 @@
         self.assertEquals(int('100', base=2), 4)
         self.assertEquals(int(x='100', base=2), 4)
 
-    # For example, PyPy 1.9.0 raised TypeError for these cases because it
-    # expects x to be a string if base is given.
-    @support.cpython_only
     def test_base_arg_with_no_x_arg(self):
-        self.assertEquals(int(base=6), 0)
-        # Even invalid bases don't raise an exception.
-        self.assertEquals(int(base=1), 0)
-        self.assertEquals(int(base=1000), 0)
-        self.assertEquals(int(base='foo'), 0)
+        self.assertRaises(TypeError, int, base=10)
+        self.assertRaises(TypeError, int, base=0)
 
     def test_non_numeric_input_types(self):
         # Test possible non-numeric types for the argument x, including
diff -r 76c5f3371db6 Objects/longobject.c
--- a/Objects/longobject.c	Sun Dec 23 15:35:23 2012 -0800
+++ b/Objects/longobject.c	Mon Dec 24 11:41:33 2012 +0200
@@ -4256,8 +4256,14 @@
     if (!PyArg_ParseTupleAndKeywords(args, kwds, "|OO:int", kwlist,
                                      &x, &obase))
         return NULL;
-    if (x == NULL)
+    if (x == NULL) {
+        if (obase != NULL) {
+            PyErr_SetString(PyExc_TypeError,
+                            "int() missing string argument");
+            return NULL;
+        }
         return PyLong_FromLong(0L);
+    }
     if (obase == NULL)
         return PyNumber_Long(x);
 
@@ -4266,7 +4272,7 @@
         return NULL;
     if (overflow || (base != 0 && base < 2) || base > 36) {
         PyErr_SetString(PyExc_ValueError,
-                        "int() arg 2 must be >= 2 and <= 36");
+                        "int() base must be >= 2 and <= 36");
         return NULL;
     }