diff --git a/pep-0307.txt b/pep-0307.txt
index 52e748fd4..647de8172 100644
--- a/pep-0307.txt
+++ b/pep-0307.txt
@@ -133,10 +133,11 @@ Extended __reduce__ API
     in this PEP.  The items are, in order:
 
     function     A callable object (not necessarily a function) called
-                 to create the initial version of the object; state may
-                 be added to the object later to fully reconstruct the
-                 pickled state.  This function must itself be
-                 picklable.
+                 to create the initial version of the object; state
+                 may be added to the object later to fully reconstruct
+                 the pickled state.  This function must itself be
+                 picklable.  See the section about __newobj__ for a
+                 special case (new in this PEP) here.
 
     arguments    A tuple giving the argument list for the function.
                  As a special case, designed for Zope 2's
@@ -184,6 +185,32 @@ Extended __reduce__ API
     state with value None.
 
 
+The __newobj__ unpickling function
+
+    When the unpickling function returned by __reduce__ (the first
+    item of the returned tuple) has the name __newobj__, something
+    special happens for pickle protocol 2.  An unpickling function
+    named __newobj__ is assumed to have the following semantics:
+
+      def __newobj__(cls, *args):
+          return cls.__new__(cls, *args)
+
+    Pickle protocol 2 special-cases an unpickling function with this
+    name, and emits a pickling opcode that, given 'cls' and 'args',
+    will return cls.__new__(cls, *args) without also pickling a
+    reference to __newobj__.  This is the main reason why protocol 2
+    pickles are so much smaller than classic pickles.  Of course, the
+    pickling code cannot verify that a function named __newobj__
+    actually has the expected semantics.  If you use an unpickling
+    function named __newobj__ that returns something different, you
+    deserve what you get.
+
+
+TBD
+
+    The rest of this PEP is still under construction!
+
+
 Copyright
 
     This document has been placed in the public domain.