diff --git a/newlib/ChangeLog b/newlib/ChangeLog
index 09843bf33..c24d76cfe 100644
--- a/newlib/ChangeLog
+++ b/newlib/ChangeLog
@@ -1,3 +1,8 @@
+2004-09-16  Antony King  <antony.king@st.com>
+
+	* libc/time/tzlock.c: Add default stubs that use generic
+	locking code.
+
 2004-09-16  Antony King  <antony.king@st.com>
 
 	* libc/ctype/ctype.tex: Added missing documentation.
diff --git a/newlib/libc/time/tzlock.c b/newlib/libc/time/tzlock.c
index 66fa1c366..f3c289620 100644
--- a/newlib/libc/time/tzlock.c
+++ b/newlib/libc/time/tzlock.c
@@ -17,13 +17,14 @@ TRAD_SYNOPSIS
 	void __tz_unlock();
 
 DESCRIPTION
-The <<tzset>> facility functions call these functions when they need
-to ensure the values of global variables.  The version of these routines supplied
-in the library do not do anything.  If multiple threads of execution
-can call the time functions and give up scheduling in the middle, then you
-you need to define your own versions of these functions in order to
-safely lock the time zone variables during a call.  If you do not, the results
-of <<localtime>>, <<mktime>>, <<ctime>>, and <<strftime>> are undefined.
+The <<tzset>> facility functions call these functions when they need to
+ensure the values of global variables.  The version of these routines
+supplied in the library use the lock API defined in sys/lock.h.  If multiple
+threads of execution can call the time functions and give up scheduling in
+the middle, then you you need to define your own versions of these functions
+in order to safely lock the time zone variables during a call.  If you do
+not, the results of <<localtime>>, <<mktime>>, <<ctime>>, and <<strftime>>
+are undefined.
 
 The lock <<__tz_lock>> may not be called recursively; that is,
 a call <<__tz_lock>> will always lock all subsequent <<__tz_lock>> calls
@@ -32,13 +33,24 @@ until the corresponding <<__tz_unlock>> call on the same thread is made.
 
 #include <_ansi.h>
 #include "local.h"
+#include <sys/lock.h>
+
+#ifndef __SINGLE_THREAD__
+__LOCK_INIT(static, __tz_lock_object);
+#endif
 
 _VOID
 _DEFUN_VOID (__tz_lock)
 {
+#ifndef __SINGLE_THREAD__
+  __lock_acquire(__tz_lock_object);
+#endif
 }
 
 _VOID
 _DEFUN_VOID (__tz_unlock)
 {
+#ifndef __SINGLE_THREAD__
+  __lock_release(__tz_lock_object);
+#endif
 }