diff --git a/ChangeLog b/ChangeLog
index f53f8ba9b7..2e848b7d4f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Sun May 29 17:53:03 2011  CHIKANAGA Tomoyuki  <nagachika00@gmail.com>
+
+	* numeric.c: add #include "interna.h" for rb_big_uminus() prototype.
+
 Sun May 29 15:09:05 2011  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* numeric.c (flo_round): fix for negative value.
diff --git a/numeric.c b/numeric.c
index fd77ff980a..09860dc6f2 100644
--- a/numeric.c
+++ b/numeric.c
@@ -12,6 +12,7 @@
 #include "ruby/ruby.h"
 #include "ruby/encoding.h"
 #include "ruby/util.h"
+#include "internal.h"
 #include <ctype.h>
 #include <math.h>
 #include <stdio.h>