diff --git a/ChangeLog b/ChangeLog
index ad0759df67..865a9b30d5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Wed Jun 27 21:28:59 2012  Kazuhiro NISHIYAMA  <zn@mbf.nifty.com>
+
+	* lib/racc/parser.rb: NotImplementError is not exist.
+
+	* lib/irb/output-method.rb (IRB::OutputMethod#print): ditto.
+
 Wed Jun 27 21:31:13 2012  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* class.c (rb_prepend_module): ancestors of prepending module also
diff --git a/lib/irb/output-method.rb b/lib/irb/output-method.rb
index 9cccda1c6a..7c0df935a9 100644
--- a/lib/irb/output-method.rb
+++ b/lib/irb/output-method.rb
@@ -19,7 +19,7 @@ module IRB
     @RCS_ID='-$Id$-'
 
     def print(*opts)
-      IRB.fail NotImplementError, "print"
+      IRB.fail NotImplementedError, "print"
     end
 
     def printn(*opts)
diff --git a/lib/racc/parser.rb b/lib/racc/parser.rb
index 737b0fda5d..e0b77f157e 100644
--- a/lib/racc/parser.rb
+++ b/lib/racc/parser.rb
@@ -11,10 +11,6 @@
 # without restriction.
 #
 
-unless defined?(NotImplementedError)
-  NotImplementedError = NotImplementError
-end
-
 module Racc
   class ParseError < StandardError; end
 end