diff --git a/ChangeLog b/ChangeLog
index 99e1187f9d..4c98a41b2c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Sun Feb 11 05:39:47 2007  Akinori MUSHA  <knu@iDaemons.org>
+
+	* lib/thread.rb: Remove an ineffective part of the code.
+
 Sun Feb 11 05:32:54 2007  Akinori MUSHA  <knu@iDaemons.org>
 
 	* ext/thread/thread.c (rb_thread_exclusive): Implement
diff --git a/lib/thread.rb b/lib/thread.rb
index 4c6a651a56..c4bb141ce7 100644
--- a/lib/thread.rb
+++ b/lib/thread.rb
@@ -12,15 +12,6 @@ unless defined? Thread
   fail "Thread not available for this ruby interpreter"
 end
 
-unless defined? ThreadError
-  class ThreadError<StandardError
-  end
-end
-
-if $DEBUG
-  Thread.abort_on_exception = true
-end
-
 class Thread
   #
   # Wraps a block in Thread.critical, restoring the original value upon exit