diff -r 2976d81a9ac9 Cython/Compiler/Builtin.py
--- a/Cython/Compiler/Builtin.py	Thu Oct 02 12:33:14 2008 -0400
+++ b/Cython/Compiler/Builtin.py	Thu Oct 02 13:37:52 2008 -0400
@@ -105,13 +105,22 @@ builtin_types_table = [
                                     ("keys",  "O",   "O", "PyDict_Keys"),
                                     ("values","O",   "O", "PyDict_Values")]),
 
-    ("set",       "PySet_Type",       []),
+    #("set",       "PySet_Type",       []),
     ("frozenset", "PyFrozenSet_Type", []),
 
     ("slice",   "PySlice_Type",    []),
     ("file",    "PyFile_Type",     []),
 
 ]
+
+import types
+if hasattr(types, 'GetSetDescriptorType'):
+    builtin_types_table.append(
+        ("set",       "PySet_Type", [("clear",   "O",  "i", "PySet_Clear"), 
+                                    ("discard", "OO", "i", "PySet_Discard"),
+                                    ("add",     "OO", "i", "PySet_Add"),
+                                    ("pop",     "O",  "O", "PySet_Pop")])
+        )
 
 builtin_structs_table = [
     ('Py_buffer', 'Py_buffer',
diff -r 2976d81a9ac9 Cython/Compiler/PyrexTypes.py
--- a/Cython/Compiler/PyrexTypes.py	Thu Oct 02 12:33:14 2008 -0400
+++ b/Cython/Compiler/PyrexTypes.py	Thu Oct 02 13:37:52 2008 -0400
@@ -295,7 +295,10 @@ class BuiltinObjectType(PyObjectType):
         return type.is_pyobject and self.assignable_from(type)
         
     def type_test_code(self, arg):
-        return 'likely(Py%s_CheckExact(%s)) || (%s) == Py_None || (PyErr_Format(PyExc_TypeError, "Expected %s, got %%s", Py_TYPE(%s)->tp_name), 0)' % (self.name[0].upper() + self.name[1:], arg, arg, self.name, arg)
+        type = self.name.capitalize()
+        if type == 'Set':
+            type = 'AnySet'
+        return 'likely(Py%s_CheckExact(%s)) || (%s) == Py_None || (PyErr_Format(PyExc_TypeError, "Expected %s, got %%s", Py_TYPE(%s)->tp_name), 0)' % (type, arg, arg, self.name, arg)
 
     def declaration_code(self, entity_code, 
             for_display = 0, dll_linkage = None, pyrex = 0):