diff --git a/ChangeLog b/ChangeLog
index 5592dfb261..6dcf96f7ba 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,7 +1,12 @@
+Tue May 14 03:22:51 2013  Koichi Sasada  <ko1@atdot.net>
+
+	* include/ruby/ruby.h: enable to generate write barrier protected
+	  arrays (T_ARRAY).
+
 Tue May 14 03:21:42 2013  Koichi Sasada  <ko1@atdot.net>
 
 	* include/ruby/ruby.h: enable to generate write barrier protected
-	  objects (T_STRING).
+	  strings (T_STRING).
 
 Tue May 14 03:19:59 2013  Koichi Sasada  <ko1@atdot.net>
 
diff --git a/include/ruby/ruby.h b/include/ruby/ruby.h
index cbc7ad1a3c..d3eb691ec5 100644
--- a/include/ruby/ruby.h
+++ b/include/ruby/ruby.h
@@ -686,7 +686,7 @@ VALUE rb_obj_setup(VALUE obj, VALUE klass, VALUE type);
 #endif
 
 #ifndef RGENGC_WB_PROTECTED_ARRAY
-#define RGENGC_WB_PROTECTED_ARRAY 0
+#define RGENGC_WB_PROTECTED_ARRAY 1
 #endif
 #ifndef RGENGC_WB_PROTECTED_STRING
 #define RGENGC_WB_PROTECTED_STRING 1