diff --git a/winsup/w32api/ChangeLog b/winsup/w32api/ChangeLog
index c923ec3c0..acbdbca78 100644
--- a/winsup/w32api/ChangeLog
+++ b/winsup/w32api/ChangeLog
@@ -1,3 +1,7 @@
+2003-07-17  Pierre Humblet  <pierre.humblet@ieee.org>
+
+	* include/mmsystem.h (TIME_KILL_SYNCHRONOUS): Add define.
+
 2003-07-17  Danny Smith <dannysmith@users.sourceforge.net>
 
 	Clean up warnings in ddk.
diff --git a/winsup/w32api/include/mmsystem.h b/winsup/w32api/include/mmsystem.h
index 81ff96ace..15ed4c01f 100644
--- a/winsup/w32api/include/mmsystem.h
+++ b/winsup/w32api/include/mmsystem.h
@@ -382,6 +382,9 @@ extern "C" {
 #define TIME_CALLBACK_FUNCTION 0
 #define TIME_CALLBACK_EVENT_SET 16
 #define TIME_CALLBACK_EVENT_PULSE 32
+#if (WINVER >= 0x0501)
+#define TIME_KILL_SYNCHRONOUS 0x0100
+#endif
 #define JOYERR_NOERROR (0)
 #define JOYERR_PARMS (JOYERR_BASE+5)
 #define JOYERR_NOCANDO (JOYERR_BASE+6)