Index: Lib/test/test_exceptions.py
===================================================================
--- Lib/test/test_exceptions.py	(revision 54643)
+++ Lib/test/test_exceptions.py	(working copy)
@@ -339,7 +339,25 @@
         self.failUnless(str(Exception('a')))
         self.failUnless(unicode(Exception(u'a')))
 
+    def testUserExceptionPickling(self):
+        # Pickling used to fail when an Exception class required
+        # an argument in the constructor, but didn't call its base
+        # class' constructor.
+        e = E("message")
+        def test(e):
+            self.assertEquals(e.message, "")
+            self.assertEquals(e.args, ("message",))
+            self.assertEquals(e.something, "message")
+        test(e)
+        for p in pickle, cPickle:
+            for protocol in range(p.HIGHEST_PROTOCOL + 1):
+                new = p.loads(p.dumps(e, protocol))
+                test(new)
 
+class E(Exception):
+    def __init__(self, something):
+        self.something = something
+
 def test_main():
     run_unittest(ExceptionTests)
 
Index: Objects/exceptions.c
===================================================================
--- Objects/exceptions.c	(revision 54643)
+++ Objects/exceptions.c	(working copy)
@@ -36,11 +36,8 @@
     /* the dict is created on the fly in PyObject_GenericSetAttr */
     self->message = self->dict = NULL;
 
-    self->args = PyTuple_New(0);
-    if (!self->args) {
-        Py_DECREF(self);
-        return NULL;
-    }
+    Py_INCREF(args);
+    self->args = args;
 
     self->message = PyString_FromString("");
     if (!self->message) {
@@ -1998,7 +1995,7 @@
 PyMODINIT_FUNC
 _PyExc_Init(void)
 {
-    PyObject *m, *bltinmod, *bdict;
+    PyObject *m, *bltinmod, *bdict, *args;
 
     PRE_INIT(BaseException)
     PRE_INIT(Exception)
@@ -2121,7 +2118,11 @@
     POST_INIT(ImportWarning)
     POST_INIT(UnicodeWarning)
 
-    PyExc_MemoryErrorInst = BaseException_new(&_PyExc_MemoryError, NULL, NULL);
+    args = PyTuple_New(0);
+    if (args == NULL)
+        Py_FatalError("Cannot pre-allocate MemoryError instance's args\n");
+    PyExc_MemoryErrorInst = BaseException_new(&_PyExc_MemoryError, args, NULL);
+    Py_DECREF(args);
     if (!PyExc_MemoryErrorInst)
         Py_FatalError("Cannot pre-allocate MemoryError instance\n");