diff --git a/ChangeLog b/ChangeLog
index c757450403..90557a5da0 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Fri Aug  8 23:27:03 2008  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* io.c (shutdown): not define if defined already.
+
 Fri Aug  8 22:47:26 2008  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* vm_insnhelper.c (opt_eq_func): large function to make inline.
diff --git a/io.c b/io.c
index 380755a599..77b85de9e3 100644
--- a/io.c
+++ b/io.c
@@ -199,7 +199,7 @@ static int max_file_descriptor = NOFILE;
 #  endif
 #endif
 
-#ifndef HAVE_SHUTDOWN
+#if !defined HAVE_SHUTDOWN && !defined shutdown
 #define shutdown(a,b)	0
 #endif