diff --git a/ChangeLog b/ChangeLog
index cb78943c6d..35bba78eb2 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Sat Oct  4 19:02:36 2008  Tadayoshi Funaba  <tadf@dotrb.org>
+
+	* lib/date/format.rb: no need to require the "lib/rational.rb".
+
 Sat Oct  4 19:02:59 2008  NARUSE, Yui  <naruse@ruby-lang.org>
 
 	* ext/nkf/nkf.c (rb_nkf_enc_get): don't replicate encoding.
diff --git a/lib/date/format.rb b/lib/date/format.rb
index baba8dcbf6..c8bc10fbac 100644
--- a/lib/date/format.rb
+++ b/lib/date/format.rb
@@ -1,8 +1,6 @@
 # format.rb: Written by Tadayoshi Funaba 1999-2008
 # $Id: format.rb,v 2.43 2008-01-17 20:16:31+09 tadf Exp $
 
-require 'rational'
-
 class Date
 
   module Format # :nodoc: