diff --git a/Lib/test/test_datetime.py b/Lib/test/test_datetime.py
index ead8d70..a971c68 100644
--- a/Lib/test/test_datetime.py
+++ b/Lib/test/test_datetime.py
@@ -3,7 +3,7 @@
 See http://www.zope.org/Members/fdrake/DateTimeWiki/TestCases
 """
 
-import os
+import sys
 import pickle
 import unittest
 
@@ -1496,7 +1496,7 @@
 
     def test_negative_float_fromtimestamp(self):
         # Windows doesn't accept negative timestamps
-        if os.name == "nt":
+        if sys.platform == "win32":
             return
         # The result is tz-dependent; at least test that this doesn't
         # fail (like it did before bug 1646728 was fixed).
@@ -1504,7 +1504,7 @@
 
     def test_negative_float_utcfromtimestamp(self):
         # Windows doesn't accept negative timestamps
-        if os.name == "nt":
+        if sys.platform == "win32":
             return
         d = self.theclass.utcfromtimestamp(-1.05)
         self.assertEquals(d, self.theclass(1969, 12, 31, 23, 59, 58, 950000))