diff -r 76e9c3e876d4 Lib/test/test_math.py
--- a/Lib/test/test_math.py	Sun May 29 20:46:27 2011 +0200
+++ b/Lib/test/test_math.py	Sun Jun 05 11:03:39 2011 +0900
@@ -335,21 +335,34 @@
 
     @requires_IEEE_754
     def testCopysign(self):
-        self.assertEqual(math.copysign(1, 42), 1.0)
+        self.assertEqual(math.copysign(1, 42), 1)
+        self.assertEqual(math.copysign(1, -42), -1)
         self.assertEqual(math.copysign(0., 42), 0.0)
         self.assertEqual(math.copysign(1., -42), -1.0)
-        self.assertEqual(math.copysign(3, 0.), 3.0)
+        self.assertEqual(math.copysign(3, 0.), 3)
         self.assertEqual(math.copysign(4., -0.), -4.0)
+        # for big integer
+        n = 10 ** 100
+        self.assertEqual(n + 1, math.copysign(-(n + 1), 1))
+        self.assertEqual(-(n + 1), math.copysign(n + 1, -1))
 
         self.assertRaises(TypeError, math.copysign)
         # copysign should let us distinguish signs of zeros
+        self.assertEqual(math.copysign(1, 0), 1)
+        self.assertEqual(math.copysign(-1, 0), -1)
         self.assertEqual(math.copysign(1., 0.), 1.)
+        self.assertEqual(math.copysign(-1., 0.), -1.)
+        self.assertEqual(math.copysign(1, 0.), 1)
+        self.assertEqual(math.copysign(-1, 0.), -1)
+        self.assertEqual(math.copysign(1, -0.), -1)
         self.assertEqual(math.copysign(1., -0.), -1.)
         self.assertEqual(math.copysign(INF, 0.), INF)
         self.assertEqual(math.copysign(INF, -0.), NINF)
         self.assertEqual(math.copysign(NINF, 0.), INF)
         self.assertEqual(math.copysign(NINF, -0.), NINF)
         # and of infinities
+        self.assertEqual(math.copysign(1, INF), 1)
+        self.assertEqual(math.copysign(1, NINF), -1)
         self.assertEqual(math.copysign(1., INF), 1.)
         self.assertEqual(math.copysign(1., NINF), -1.)
         self.assertEqual(math.copysign(INF, INF), INF)
@@ -364,6 +377,8 @@
         # we don't know whether the sign bit of NAN is set on any
         # given platform.
         self.assertTrue(math.isinf(math.copysign(INF, NAN)))
+        # similarly, copysign(2, NAN) could be 2 or -2
+        self.assertEqual(abs(math.copysign(2, NAN)), 2)
         # similarly, copysign(2., NAN) could be 2. or -2.
         self.assertEqual(abs(math.copysign(2., NAN)), 2.)
 
diff -r 76e9c3e876d4 Modules/mathmodule.c
--- a/Modules/mathmodule.c	Sun May 29 20:46:27 2011 +0200
+++ b/Modules/mathmodule.c	Sun Jun 05 11:03:39 2011 +0900
@@ -821,14 +821,35 @@
 static PyObject *
 math_2(PyObject *args, double (*func) (double, double), char *funcname)
 {
-    PyObject *ox, *oy;
+    PyObject *ox, *oy, *or, *zero, *absox;
     double x, y, r;
     if (! PyArg_UnpackTuple(args, funcname, 2, 2, &ox, &oy))
         return NULL;
     x = PyFloat_AsDouble(ox);
     y = PyFloat_AsDouble(oy);
-    if ((x == -1.0 || y == -1.0) && PyErr_Occurred())
+    if ((x == -1.0 || y == -1.0) && PyErr_Occurred()) {
+        PyErr_SetString(PyExc_TypeError, "a float or integer is required");
         return NULL;
+    }
+    if (strcmp(funcname, "copysign") == 0 && PyLong_Check(ox)) {
+        absox = PyNumber_Absolute(ox);
+        zero = PyLong_FromLong(0);
+      // occur error
+      //if (_PyLong_Sign(oy) < 0)
+        if (((PyFloatObject *)oy)->ob_fval < 0)
+            printf("((PyFloatObject *)oy)->ob_fval < 0\n");
+        else
+            printf("((PyFloatObject *)oy)->ob_fval >= 0\n");
+        if (PyObject_RichCompareBool(oy, zero, Py_LT))
+            or = PyNumber_Negative(absox);
+        else if (PyObject_RichCompareBool(oy, zero, Py_GT))
+            or = PyNumber_Positive(absox);
+        else
+            or = PyNumber_Long(ox);
+        Py_DECREF(zero);
+        Py_DECREF(absox);
+        return or;
+    }
     errno = 0;
     PyFPE_START_PROTECT("in math_2", return 0);
     r = (*func)(x, y);