Index: Objects/exceptions.c
===================================================================
--- Objects/exceptions.c	(revision 56094)
+++ Objects/exceptions.c	(working copy)
@@ -145,14 +145,69 @@
 
 /* Pickling support */
 static PyObject *
-BaseException_reduce(PyBaseExceptionObject *self)
+common_exception_reduce_ex(PyBaseExceptionObject *self, PyObject **dict_out)
 {
-    if (self->args && self->dict)
-        return PyTuple_Pack(3, self->ob_type, self->args, self->dict);
-    else
-        return PyTuple_Pack(2, self->ob_type, self->args);
+    PyObject *result = NULL;
+    PyObject *constructor = NULL;
+    PyObject *constructor_args = NULL;
+    PyObject *state = NULL;
+    PyObject *copy_reg = NULL;
+
+    copy_reg = PyImport_ImportModule("copy_reg");
+    if (copy_reg == NULL) {
+        goto end;
+    }
+    
+    /* Unfortunately BaseException.__new__ is not pickleable. */
+    constructor = PyObject_GetAttrString(copy_reg, "_exception_constructor");
+    if (constructor == NULL) {
+        goto end;
+    }
+    
+    constructor_args = PyTuple_Pack(1, self->ob_type);
+    if (constructor_args == NULL) {
+        goto end;
+    }
+    
+    state = PyDict_New();
+    if (state == NULL) {
+        goto end;
+    }
+    if (self->dict) {
+        if (PyDict_Update(state, self->dict)) {
+            goto end;
+        }
+    }
+    if (PyDict_SetItemString(state, "args", self->args)) {
+        goto end;
+    }
+    if (PyDict_SetItemString(state, "message", self->message)) {
+        goto end;
+    }
+    *dict_out = state;
+
+    result = PyTuple_Pack(3, constructor, constructor_args, state);
+end:
+    Py_XDECREF(constructor);
+    Py_XDECREF(constructor_args);
+    Py_XDECREF(state);
+    Py_XDECREF(copy_reg);
+    return result;
 }
 
+static PyObject *
+BaseException_reduce_ex(PyBaseExceptionObject *self, PyObject *proto)
+{
+    PyObject *result;
+    PyObject *state;
+    
+    result = common_exception_reduce_ex(self, &state);
+    if (result == NULL) {
+        return NULL;
+    }
+    return result;
+}
+
 /*
  * Needed for backward compatibility, since exceptions used to store
  * all their attributes in the __dict__. Code is taken from cPickle's
@@ -179,7 +234,7 @@
 
 
 static PyMethodDef BaseException_methods[] = {
-   {"__reduce__", (PyCFunction)BaseException_reduce, METH_NOARGS },
+   {"__reduce_ex__", (PyCFunction)BaseException_reduce_ex, METH_O },
    {"__setstate__", (PyCFunction)BaseException_setstate, METH_O },
    {NULL, NULL, 0, NULL},
 };
@@ -700,41 +755,36 @@
 
 
 static PyObject *
-EnvironmentError_reduce(PyEnvironmentErrorObject *self)
+EnvironmentError_reduce_ex(PyEnvironmentErrorObject *self, PyObject *proto)
 {
-    PyObject *args = self->args;
-    PyObject *res = NULL, *tmp;
+    PyObject *result;
+    PyObject *state;
+    
+    result = common_exception_reduce_ex((PyBaseExceptionObject *)self, &state);
+    if (result == NULL) {
+        return NULL;
+    }
+    if (PyDict_SetItemString(state, "errno", self->myerrno)) {
+        Py_DECREF(result);
+        return NULL;
+    }
+    if (PyDict_SetItemString(state, "strerror", self->strerror)) {
+        Py_DECREF(result);
+        return NULL;
+    }
+    if (self->filename) {
+        if (PyDict_SetItemString(state, "filename", self->filename)) {
+            Py_DECREF(result);
+            return NULL;
+        }
+    }
 
-    /* self->args is only the first two real arguments if there was a
-     * file name given to EnvironmentError. */
-    if (PyTuple_GET_SIZE(args) == 2 && self->filename) {
-        args = PyTuple_New(3);
-        if (!args) return NULL;
-
-        tmp = PyTuple_GET_ITEM(self->args, 0);
-        Py_INCREF(tmp);
-        PyTuple_SET_ITEM(args, 0, tmp);
-
-        tmp = PyTuple_GET_ITEM(self->args, 1);
-        Py_INCREF(tmp);
-        PyTuple_SET_ITEM(args, 1, tmp);
-
-        Py_INCREF(self->filename);
-        PyTuple_SET_ITEM(args, 2, self->filename);
-    } else
-        Py_INCREF(args);
-
-    if (self->dict)
-        res = PyTuple_Pack(3, self->ob_type, args, self->dict);
-    else
-        res = PyTuple_Pack(2, self->ob_type, args);
-    Py_DECREF(args);
-    return res;
+    return result;
 }
 
 
 static PyMethodDef EnvironmentError_methods[] = {
-    {"__reduce__", (PyCFunction)EnvironmentError_reduce, METH_NOARGS},
+    {"__reduce_ex__", (PyCFunction)EnvironmentError_reduce_ex, METH_O},
     {NULL}
 };
 
Index: Lib/copy_reg.py
===================================================================
--- Lib/copy_reg.py	(revision 56094)
+++ Lib/copy_reg.py	(working copy)
@@ -41,6 +41,10 @@
 
     pickle(complex, pickle_complex, complex)
 
+# This is here because pickle can't pickle BaseException.__new__ directly.
+def _exception_constructor(cls):
+    return BaseException.__new__(cls)
+
 # Support for pickling new-style objects
 
 def _reconstructor(cls, base, state):