diff --git a/ChangeLog b/ChangeLog
index 2a629260e0..97e8e79900 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Thu Jan  6 05:25:49 2011  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* array.c (rb_ary_modify): export.
+
 Thu Jan  6 05:14:41 2011  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* ext/stringio/stringio.c (get_strio, strio_set_string)
diff --git a/array.c b/array.c
index 54213449dd..43cc910cdc 100644
--- a/array.c
+++ b/array.c
@@ -247,7 +247,7 @@ rb_ary_modify_check(VALUE ary)
 	rb_raise(rb_eSecurityError, "Insecure: can't modify array");
 }
 
-static void
+void
 rb_ary_modify(VALUE ary)
 {
     rb_ary_modify_check(ary);
diff --git a/include/ruby/intern.h b/include/ruby/intern.h
index 7f194a9dd2..1e3a01b549 100644
--- a/include/ruby/intern.h
+++ b/include/ruby/intern.h
@@ -54,6 +54,7 @@ VALUE rb_ary_new3(long,...);
 VALUE rb_ary_new4(long, const VALUE *);
 VALUE rb_ary_tmp_new(long);
 void rb_ary_free(VALUE);
+void rb_ary_modify(VALUE);
 VALUE rb_ary_freeze(VALUE);
 VALUE rb_ary_aref(int, VALUE*, VALUE);
 VALUE rb_ary_subseq(VALUE, long, long);