diff --git a/ChangeLog b/ChangeLog
index e2bee6c22c..d44366b53a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -2,6 +2,9 @@ Wed Dec 17 15:44:28 2008  Yukihiro Matsumoto  <matz@ruby-lang.org>
 
 	* array.c (rb_ary_pop_m): use enum ary_take_pos_flags.
 
+	* array.c (rb_ary_push_m): add modification check before actual
+	  operation.   [ruby-dev:37440]
+
 Wed Dec 17 15:35:39 2008  Yuki Sonoda (Yugui)  <yugui@yugui.jp>
 
 	* configure.in (OBJDUMP, OBJCOPY): 
diff --git a/array.c b/array.c
index 535cfd0605..3ba450cbe9 100644
--- a/array.c
+++ b/array.c
@@ -693,6 +693,7 @@ rb_ary_push(VALUE ary, VALUE item)
 static VALUE
 rb_ary_push_m(int argc, VALUE *argv, VALUE ary)
 {
+    rb_ary_modify_check(ary);
     while (argc--) {
 	rb_ary_push(ary, *argv++);
     }