diff --git a/ChangeLog b/ChangeLog
index d34740c3e7..e7190036f3 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Sun Jan  8 01:18:19 2012  Ayumu AIZAWA  <ayumu.aizawa@gmail.com>
+
+	* test/-ext-/old_thread_select/test_old_thread_select.rb:
+	  avoid platform bug. [Bug #5858] [ruby-dev:45108]
+
 Sun Jan  8 00:46:34 2012  KOSAKI Motohiro  <kosaki.motohiro@gmail.com>
 
 	* gc.c: get rid of implicit narrowing conversion.
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 5653dbc021..340351a08e 100644
--- a/test/-ext-/old_thread_select/test_old_thread_select.rb
+++ b/test/-ext-/old_thread_select/test_old_thread_select.rb
@@ -4,6 +4,7 @@ class TestOldThreadSelect < Test::Unit::TestCase
   require '-test-/old_thread_select/old_thread_select'
 
   ANCIENT_LINUX = RUBY_PLATFORM =~ /linux/ && `uname -r`.chomp < '2.6.32'
+  DARWIN_10     = RUBY_PLATFORM =~ /darwin10/
 
   def with_pipe
     r, w = IO.pipe
@@ -87,7 +88,7 @@ class TestOldThreadSelect < Test::Unit::TestCase
       end
     end
 
-    unless ANCIENT_LINUX
+    unless ANCIENT_LINUX || DARWIN_10
       assert_operator diff, :>=, 1, "interrupted or short wait: diff=#{diff}"
     end
     assert_equal 0, rc