diff --git a/ChangeLog b/ChangeLog
index 7cb41e5716..c4f496fcc7 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Tue Nov  4 03:28:31 2008  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* array.c (rb_ary_join): do not repeat self in a recursive array.
+	  [ruby-dev:37019]
+
 Tue Nov  4 01:56:46 2008  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* include/ruby/intern.h (rb_mutex_synchronize): fixed prototype.
diff --git a/array.c b/array.c
index 237fdd25a1..2e6db452c5 100644
--- a/array.c
+++ b/array.c
@@ -1487,7 +1487,10 @@ rb_ary_join(VALUE ary, VALUE sep)
 	  case T_STRING:
 	    break;
 	  case T_ARRAY:
-	    {
+	    if (tmp == ary) {
+		tmp = rb_usascii_str_new2("[...]");
+	    }
+	    else {
 		VALUE args[2];
 
 		args[0] = tmp;