diff -r 6d278f426417 Include/pyerrors.h
--- a/Include/pyerrors.h	Fri Jul 05 18:05:29 2013 -1000
+++ b/Include/pyerrors.h	Sat Jul 06 18:52:16 2013 +0200
@@ -36,6 +36,11 @@
 
 typedef struct {
     PyException_HEAD
+    PyObject *attr;
+} PyAttributeErrorObject;
+
+typedef struct {
+    PyException_HEAD
     PyObject *encoding;
     PyObject *object;
     Py_ssize_t start;
@@ -269,6 +274,8 @@
     PyObject *);
 PyAPI_FUNC(PyObject *) PyErr_SetImportError(PyObject *, PyObject *,
     PyObject *);
+PyAPI_FUNC(PyObject *) PyErr_SetAttributeError(PyObject *, PyObject *,
+    PyObject *);
 
 /* Export the old function so that the existing API remains available: */
 PyAPI_FUNC(void) PyErr_BadInternalCall(void);
diff -r 6d278f426417 Lib/test/test_exceptions.py
--- a/Lib/test/test_exceptions.py	Fri Jul 05 18:05:29 2013 -1000
+++ b/Lib/test/test_exceptions.py	Sat Jul 06 18:52:16 2013 +0200
@@ -952,6 +952,15 @@
             exc = ImportError(arg)
             self.assertEqual(str(arg), str(exc))
 
+class AttributeErrorTests(unittest.TestCase):
+    def test_attributes(self):
+        # Setting 'attr' should not be a problem.
+        exc = AttributeError('coconut carrying')
+        self.assertIsNone(exc.attr)
+
+        exc = AttributeError('coconut carrying', attr='carry')
+        self.assertEqual(exc.attr, 'carry')
+
 
 if __name__ == '__main__':
     unittest.main()
diff -r 6d278f426417 Objects/exceptions.c
--- a/Objects/exceptions.c	Fri Jul 05 18:05:29 2013 -1000
+++ b/Objects/exceptions.c	Sat Jul 06 18:52:16 2013 +0200
@@ -1194,10 +1194,73 @@
 /*
  *    AttributeError extends Exception
  */
-SimpleExtendsException(PyExc_Exception, AttributeError,
+static int
+AttributeError_init(PyAttributeErrorObject *self, PyObject *args, PyObject *kwds)
+{
+    PyObject *attr = NULL;
+
+    if (kwds) {
+        GET_KWD(attr);
+    }
+
+    if (BaseException_init((PyBaseExceptionObject *)self, args, kwds) == -1)
+        return -1;
+
+    if (PyTuple_GET_SIZE(args) != 1)
+        return 0;
+
+
+    return 0;
+}
+
+static int
+AttributeError_clear(PyAttributeErrorObject *self)
+{
+    Py_CLEAR(self->attr);
+    return BaseException_clear((PyBaseExceptionObject *)self);
+}
+
+static void
+AttributeError_dealloc(PyAttributeErrorObject *self)
+{
+    _PyObject_GC_UNTRACK(self);
+    AttributeError_clear(self);
+    Py_TYPE(self)->tp_free((PyObject *)self);
+}
+
+static int
+AttributeError_traverse(PyAttributeErrorObject *self, visitproc visit, void *arg)
+{
+    Py_VISIT(self->attr);
+    return BaseException_traverse((PyBaseExceptionObject *)self, visit, arg);
+}
+
+static PyObject *
+AttributeError_str(PyAttributeErrorObject *self)
+{
+    return BaseException_str((PyBaseExceptionObject *)self);
+}
+
+static PyMemberDef AttributeError_members[] = {
+    {"attr", T_OBJECT, offsetof(PyAttributeErrorObject, attr), 0,
+        PyDoc_STR("attribute name")},
+    {NULL}  /* Sentinel */
+};
+
+static PyMethodDef AttributeError_methods[] = {
+    {NULL}
+};
+
+
+ComplexExtendsException(PyExc_Exception, AttributeError,
+			AttributeError, 0,
+			AttributeError_methods, AttributeError_members,
+			0, AttributeError_str,
                        "Attribute not found.");
 
 
+
+
 /*
  *    SyntaxError extends Exception
  */