diff --git a/ChangeLog b/ChangeLog
index d602eccbb1..c872696f73 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Mon Jan 14 23:33:02 2008  NARUSE, Yui  <naruse@ruby-lang.org>
+
+	* ext/nkf/lib/kconv.rb (Kconv.tolocale): argument is str.
+
 Mon Jan 14 23:31:05 2008  Yukihiro Matsumoto  <matz@ruby-lang.org>
 
 	* configure.in (setup): add -I$(EXTOUT)/$(arch) to MINIRUBY.
diff --git a/ext/nkf/lib/kconv.rb b/ext/nkf/lib/kconv.rb
index 159a5aa233..81a8a4b72b 100644
--- a/ext/nkf/lib/kconv.rb
+++ b/ext/nkf/lib/kconv.rb
@@ -124,7 +124,7 @@ module Kconv
   #    Kconv.tolocale   => string
   #
   # Convert <code>self</code> to locale encoding
-  def tolocale
+  def tolocale(str)
     kconv(str, Encoding.locale_charmap)
   end
   module_function :tolocale