diff --git a/ChangeLog b/ChangeLog
index 1a850f54a0..b891b206fd 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Sat Nov 10 00:46:57 2012  Naohisa Goto  <ngotogenome@gmail.com>
+
+	* atomic.h: Revert r37491 which is a temporary workaroud.
+
 Sat Nov 10 00:33:31 2012  NAKAMURA Usaku  <usa@ruby-lang.org>
 
 	* siphash.h: check configure macros before include newer headers.
diff --git a/atomic.h b/atomic.h
index 4a5ba188b1..f4dd5db38a 100644
--- a/atomic.h
+++ b/atomic.h
@@ -65,7 +65,6 @@ rb_w32_atomic_or(volatile rb_atomic_t *var, rb_atomic_t val)
 
 #elif defined(__sun)
 #include <atomic.h>
-#include <sys/atomic.h>
 typedef unsigned int rb_atomic_t;
 
 # define ATOMIC_SET(var, val) (void)atomic_swap_uint(&(var), (val))