diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index ea65bf529..01e2a7625 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,7 @@
+2009-10-09  Corinna Vinschen  <corinna@vinschen.de>
+
+	* include/cygwin/config.h (DEFAULT_LOCALE): Define as "C.UTF-8".
+
 2009-10-08  Christopher Faylor  <me+cygwin@cgf.cx>
 
 	* exceptions.cc (_cygtls::signal_exit): There's no need to set
diff --git a/winsup/cygwin/include/cygwin/config.h b/winsup/cygwin/include/cygwin/config.h
index da82c1dec..4404a9473 100644
--- a/winsup/cygwin/include/cygwin/config.h
+++ b/winsup/cygwin/include/cygwin/config.h
@@ -67,6 +67,8 @@ extern char *_tlsbase __asm__ ("%fs:4");
 #define __WCHAR_MAX__ 0xffffu
 #endif
 
+#define DEFAULT_LOCALE "C.UTF-8"
+
 #ifdef __cplusplus
 }
 #endif