diff --git a/Lib/inspect.py b/Lib/inspect.py
index dc2fa08..0cbf521 100644
--- a/Lib/inspect.py
+++ b/Lib/inspect.py
@@ -89,6 +89,40 @@
     is not guaranteed."""
     return (hasattr(object, "__set__") and hasattr(object, "__get__"))
 
+if hasattr(types, 'MemberDescriptorType'):
+    # CPython and equivalent
+    def ismemberdescriptor(object):
+        """Return true if the object is a member descriptor.
+
+        Member descriptors are specialized descriptors defined in extension
+        modules."""
+        return isinstance(object, types.MemberDescriptorType)
+else:
+    # Other implementations
+    def ismemberdescriptor(object):
+        """Return true if the object is a member descriptor.
+
+        Member descriptors are specialized descriptors defined in extension
+        modules."""
+        return False
+
+if hasattr(types, 'GetSetDescriptorType'):
+    # CPython and equivalent
+    def isgetsetdescriptor(object):
+        """Return true if the object is a getset descriptor.
+
+        getset descriptors are specialized descriptors defined in extension
+        modules."""
+        return isinstance(object, types.GetSetDescriptorType)
+else:
+    # Other implementations
+    def isgetsetdescriptor(object):
+        """Return true if the object is a getset descriptor.
+
+        getset descriptors are specialized descriptors defined in extension
+        modules."""
+        return False
+        
 def isfunction(object):
     """Return true if the object is a user-defined function.
 
diff --git a/Lib/pydoc.py b/Lib/pydoc.py
index ff6e7ca..0fc624e 100755
--- a/Lib/pydoc.py
+++ b/Lib/pydoc.py
@@ -318,6 +318,8 @@
         # identifies something in a way that pydoc itself has issues handling;
         # think 'super' and how it is a descriptor (which raises the exception
         # by lacking a __name__ attribute) and an instance.
+        if inspect.isgetsetdescriptor(object): return self.docdata(*args)
+        if inspect.ismemberdescriptor(object): return self.docdata(*args)
         try:
             if inspect.ismodule(object): return self.docmodule(*args)
             if inspect.isclass(object): return self.docclass(*args)
@@ -333,7 +335,7 @@
             name and ' ' + repr(name), type(object).__name__)
         raise TypeError, message
 
-    docmodule = docclass = docroutine = docother = fail
+    docmodule = docclass = docroutine = docother = docproperty = docdata = fail
 
     def getdocloc(self, object):
         """Return the location of module docs or None"""
@@ -915,6 +917,10 @@
         lhs = name and '<strong>%s</strong> = ' % name or ''
         return lhs + self.repr(object)
 
+    def docdata(self, object, name=None, mod=None, cl=None):
+        """Produce html documentation for a data descriptor."""
+        return self._docdescriptor(name, object, mod)
+
     def index(self, dir, shadowed=None):
         """Generate an HTML index for a directory of modules."""
         modpkgs = []
@@ -1268,6 +1274,10 @@
         """Produce text documentation for a property."""
         return self._docdescriptor(name, object, mod)
 
+    def docdata(self, object, name=None, mod=None, cl=None):
+        """Produce text documentation for a data descriptor."""
+        return self._docdescriptor(name, object, mod)
+
     def docother(self, object, name=None, mod=None, parent=None, maxlen=None, doc=None):
         """Produce text documentation for a data object."""
         repr = self.repr(object)
@@ -1397,6 +1407,14 @@
             return 'module ' + thing.__name__
     if inspect.isbuiltin(thing):
         return 'built-in function ' + thing.__name__
+    if inspect.isgetsetdescriptor(thing):
+        return 'getset descriptor %s.%s.%s' % (
+            thing.__objclass__.__module__, thing.__objclass__.__name__,
+            thing.__name__)
+    if inspect.ismemberdescriptor(thing):
+        return 'member descriptor %s.%s.%s' % (
+            thing.__objclass__.__module__, thing.__objclass__.__name__,
+            thing.__name__)
     if inspect.isclass(thing):
         return 'class ' + thing.__name__
     if inspect.isfunction(thing):
@@ -1453,6 +1471,8 @@
         if not (inspect.ismodule(object) or
                 inspect.isclass(object) or
                 inspect.isroutine(object) or
+                inspect.isgetsetdescriptor(object) or
+                inspect.ismemberdescriptor(object) or
                 isinstance(object, property)):
             # If the passed object is a piece of data or an instance,
             # document its available methods instead of its value.
diff --git a/Lib/test/test_inspect.py b/Lib/test/test_inspect.py
index 76f2566..928af07 100644
--- a/Lib/test/test_inspect.py
+++ b/Lib/test/test_inspect.py
@@ -1,6 +1,8 @@
 import sys
+import types
 import unittest
 import inspect
+import datetime
 
 from test.test_support import TESTFN, run_unittest
 
@@ -40,10 +42,11 @@
             self.failIf(other(obj), 'not %s(%s)' % (other.__name__, exp))
 
 class TestPredicates(IsTestBase):
-    def test_eleven(self):
-        # Doc/lib/libinspect.tex claims there are 11 such functions
+    def test_thirteen(self):
+        # Doc/lib/libinspect.tex claims there are 13 such functions
         count = len(filter(lambda x:x.startswith('is'), dir(inspect)))
-        self.assertEqual(count, 11, "There are %d (not 11) is* functions" % count)
+        self.assertEqual(count, 13,
+                         "There are %d (not 12) is* functions" % count)
 
     def test_excluding_predicates(self):
         self.istest(inspect.isbuiltin, 'sys.exit')
@@ -58,6 +61,15 @@
         self.istest(inspect.istraceback, 'tb')
         self.istest(inspect.isdatadescriptor, '__builtin__.file.closed')
         self.istest(inspect.isdatadescriptor, '__builtin__.file.softspace')
+        if hasattr(types, 'GetSetDescriptorType'):
+            self.istest(inspect.isgetsetdescriptor,
+                        'type(tb.tb_frame).f_locals')
+        else:
+            self.failIf(inspect.isgetsetdescriptor(type(tb.tb_frame).f_locals))
+        if hasattr(types, 'MemberDescriptorType'):
+            self.istest(inspect.ismemberdescriptor, 'datetime.timedelta.days')
+        else:
+            self.failIf(inspect.ismemberdescriptor(datetime.timedelta.days))
 
     def test_isroutine(self):
         self.assert_(inspect.isroutine(mod.spam))
diff --git a/Lib/types.py b/Lib/types.py
index 39812ac..6c8c2b2 100644
--- a/Lib/types.py
+++ b/Lib/types.py
@@ -86,4 +86,16 @@
 DictProxyType = type(TypeType.__dict__)
 NotImplementedType = type(NotImplemented)
 
-del sys, _f, _g, _C, _x                  # Not for export
+# Extension types defined in a C helper module.  XXX There may be no
+# equivalent in implementations other than CPython, so it seems better to
+# leave them undefined then to set them to e.g. None.
+try:
+    import _types
+except ImportError:
+    pass
+else:
+    GetSetDescriptorType = type(_types.Helper.getter)
+    MemberDescriptorType = type(_types.Helper.member)
+    del _types
+
+del sys, _f, _g, _C, _x                           # Not for export