diff --git a/ChangeLog b/ChangeLog
index b9867151e0..6d32460cb4 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Sun May 16 10:49:47 2010  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* ext/iconv/iconv.c (rb_iconv_sys_fail): fix number of arguments.
+	  a patch by Masaya TARUI <tarui AT prx.jp>.
+
 Sun May 16 02:24:27 2010  Yutaka Kanemoto  <kanemoto@ruby-lang.org>
 
 	* configure.in: can not load libruby.so if gcc is used with
diff --git a/ext/iconv/iconv.c b/ext/iconv/iconv.c
index a25e9cb079..ff30c4e13a 100644
--- a/ext/iconv/iconv.c
+++ b/ext/iconv/iconv.c
@@ -178,7 +178,7 @@ static void
 rb_iconv_sys_fail(const char *s)
 {
     if (errno == 0) {
-	rb_raise(rb_eIconvBrokenLibrary, "%s", s);
+	rb_exc_raise(iconv_fail(rb_eIconvBrokenLibrary, Qnil, Qnil, NULL, s));
     }
     rb_sys_fail(s);
 }