Index: Python/sysmodule.c
===================================================================
--- Python/sysmodule.c	(revision 62379)
+++ Python/sysmodule.c	(working copy)
@@ -226,6 +226,36 @@
 exit status will be one (i.e., failure)."
 );
 
+static PyObject *
+sys_setpy3kwarn(PyObject *self, PyObject *mode)
+{
+	int on;
+	on = PyObject_IsTrue(mode);
+	if (on == -1)
+		return NULL;
+	Py_Py3kWarningFlag = on;
+	Py_RETURN_NONE;
+	
+}
+
+PyDoc_STRVAR(setpy3kwarn_doc,
+"setpy3kwarn(mode)\n\
+\n\
+Enable or disable Py3k warnings."
+);
+
+static PyObject *
+sys_getpy3kwarn(PyObject *self, PyObject *args)
+{
+	return PyBool_FromLong(Py_Py3kWarningFlag);
+}
+
+PyDoc_STRVAR(getpy3kwarn_doc,
+"getpy3kwarn() -> bool\n\
+\n\
+Get whether Py3k warnings are being issued."
+);
+
 #ifdef Py_USING_UNICODE
 
 static PyObject *
@@ -846,6 +876,7 @@
 #ifdef Py_TRACE_REFS
 	{"getobjects",	_Py_GetObjects, METH_VARARGS},
 #endif
+	{"getpy3kwarn", sys_getpy3kwarn, METH_NOARGS, getpy3kwarn_doc},
 #ifdef Py_REF_DEBUG
 	{"gettotalrefcount", (PyCFunction)sys_gettotalrefcount, METH_NOARGS},
 #endif
@@ -874,6 +905,7 @@
 #endif
 	{"setprofile",	sys_setprofile, METH_O, setprofile_doc},
 	{"getprofile",	sys_getprofile, METH_NOARGS, getprofile_doc},
+	{"setpy3kwarn", sys_setpy3kwarn, METH_O, setpy3kwarn_doc},
 	{"setrecursionlimit", sys_setrecursionlimit, METH_VARARGS,
 	 setrecursionlimit_doc},
 #ifdef WITH_TSC
@@ -1349,8 +1381,6 @@
 		   	    PyString_FromString(Py_GetExecPrefix()));
 	SET_SYS_FROM_STRING("maxint",
 			    PyInt_FromLong(PyInt_GetMax()));
-	SET_SYS_FROM_STRING("py3kwarning",
-			    PyBool_FromLong(Py_Py3kWarningFlag));
 	SET_SYS_FROM_STRING("float_info",
 			    PyFloat_GetInfo());
 #ifdef Py_USING_UNICODE
Index: Doc/library/sys.rst
===================================================================
--- Doc/library/sys.rst	(revision 62378)
+++ Doc/library/sys.rst	(working copy)
@@ -430,6 +430,14 @@
    .. versionadded:: 2.6
 
 
+.. function:: getpy3kwarn()
+
+   Return the status of the Py3k warning flag.  It's ``True`` when Python is
+   started with the -3 option or enabled through :func:`setpy3kwarn`.
+
+   .. versionadded:: 2.6
+
+
 .. function:: gettrace()
 
    .. index::
@@ -611,15 +619,6 @@
    interpreter prepares to read a new interactive command; this can be used to
    implement a dynamic prompt.
 
-
-.. data:: py3kwarning
-
-   Bool containing the status of the Python 3.0 warning flag. It's ``True``
-   when Python is started with the -3 option.
-
-   .. versionadded:: 2.6
-
-
 .. data:: dont_write_bytecode
 
    If this is true, Python won't try to write ``.pyc`` or ``.pyo`` files on the
@@ -699,6 +698,13 @@
    limit can lead to a crash.
 
 
+.. function:: setpy3kwarning(mode)
+
+   Enable or or disable Py3k warnings.
+
+   .. versionadded:: 2.6
+
+
 .. function:: settrace(tracefunc)
 
    .. index::
Index: Lib/warnings.py
===================================================================
--- Lib/warnings.py	(revision 62378)
+++ Lib/warnings.py	(working copy)
@@ -16,7 +16,7 @@
 
     Warnings are omitted unless Python is started with the -3 option.
     """
-    if sys.py3kwarning:
+    if sys.getpy3kwarn():
         if category is None:
             category = DeprecationWarning
         warn(message, category, stacklevel+1)
Index: Lib/test/regrtest.py
===================================================================
--- Lib/test/regrtest.py	(revision 62378)
+++ Lib/test/regrtest.py	(working copy)
@@ -1147,9 +1147,6 @@
                 self.expected.add('test_sunaudiodev')
                 self.expected.add('test_nis')
 
-            if not sys.py3kwarning:
-                self.expected.add('test_py3kwarn')
-
             self.valid = True
 
     def isvalid(self):
Index: Lib/test/test_py3kwarn.py
===================================================================
--- Lib/test/test_py3kwarn.py	(revision 62378)
+++ Lib/test/test_py3kwarn.py	(working copy)
@@ -4,10 +4,7 @@
                                 TestSkipped)
 import warnings
 
-if not sys.py3kwarning:
-    raise TestSkipped('%s must be run with the -3 flag' % __name__)
 
-
 class TestPy3KWarnings(unittest.TestCase):
 
     def test_type_inequality_comparisons(self):
@@ -125,7 +122,13 @@
 
 
 def test_main():
-    run_unittest(TestPy3KWarnings)
+    old_warn = sys.getpy3kwarn()
+    if not old_warn:
+        sys.setpy3kwarn(True)
+    try:
+        run_unittest(TestPy3KWarnings)
+    finally:
+        sys.setpy3kwarn(old_warn)
 
 if __name__ == '__main__':
     test_main()
Index: Lib/test/test_sys.py
===================================================================
--- Lib/test/test_sys.py	(revision 62378)
+++ Lib/test/test_sys.py	(working copy)
@@ -219,6 +219,16 @@
             self.assertEqual(sys.getdlopenflags(), oldflags+1)
             sys.setdlopenflags(oldflags)
 
+    def test_py3kwarn(self):
+        old_warn = sys.getpy3kwarn()
+        sys.setpy3kwarn(True)
+        try:
+            with test.test_support.catch_warning() as w:
+                int < str
+        finally:
+            sys.setpy3kwarn(old_warn)
+        self.assert_(w.message)
+
     def test_refcount(self):
         self.assertRaises(TypeError, sys.getrefcount)
         c = sys.getrefcount(None)
@@ -354,7 +364,7 @@
 
     def test_sys_flags(self):
         self.failUnless(sys.flags)
-        attrs = ("debug", "py3k_warning", "division_warning", "division_new",
+        attrs = ("debug", "division_warning", "division_new",
                  "inspect", "interactive", "optimize", "dont_write_bytecode",
                  "no_site", "ignore_environment", "tabcheck", "verbose",
                  "unicode")