diff --git a/ChangeLog b/ChangeLog
index d3064bbef2..4c7203ad6a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+Wed Aug 31 00:30:49 2011  NAKAMURA Usaku  <usa@ruby-lang.org>
+
+	* test/-ext-/old_thread_select/test_old_thread_select.rb
+	  (TestOldThreadSelect#test_old_select_read_timeout): if the machine
+	  is fast enough, the time used by code around IO.select may be smaller
+	  than Time implement threshold.
+
 Wed Aug 31 00:04:38 2011  NAKAMURA Usaku  <usa@ruby-lang.org>
 
 	* ext/-test-/old_thread_select/old_thread_select.c (old_thread_select):
diff --git a/test/-ext-/old_thread_select/test_old_thread_select.rb b/test/-ext-/old_thread_select/test_old_thread_select.rb
index d965724c83..a7db7bdf99 100644
--- a/test/-ext-/old_thread_select/test_old_thread_select.rb
+++ b/test/-ext-/old_thread_select/test_old_thread_select.rb
@@ -19,7 +19,7 @@ class TestOldThreadSelect < Test::Unit::TestCase
       rc = IO.old_thread_select([r.fileno], nil, nil, 0.001)
       diff = Time.now - t0
       assert_equal 0, rc
-      assert diff > 0.001, "returned too early"
+      assert diff >= 0.001, "returned too early"
     end
   end