test_pre_save_untyped is time sensitive

[Wilfred]

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FAIL: test_pre_save_untyped (djangotoolbox.tests.EmbeddedModelFieldTest)
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Traceback (most recent call last):
 File "<http://freedomfry.local:8080/job/Google%20Art%20Project/ws/djangotoolbox/tests.py",> line 269, in test_pre_save_untyped
   self.test_pre_save(field='simple_untyped')
 File "<http://freedomfry.local:8080/job/Google%20Art%20Project/ws/djangotoolbox/tests.py",> line 265, in test_pre_save
   self.assertEqualDatetime(getattr(instance, field).auto_now_add, auto_now_add)
 File "<http://freedomfry.local:8080/job/Google%20Art%20Project/ws/djangotoolbox/tests.py",> line 235, in assertEqualDatetime
   self.assertEqual(d1.replace(microsecond=0), d2.replace(microsecond=0))
AssertionError: datetime.datetime(2011, 12, 15, 6, 39, 55) != datetime.datetime(2011, 12, 15, 6, 39, 54)

The system the test ran on was rather slow it seems.