diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index 0fd925de9..648c038f1 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,8 @@
+2002-12-19  Pierre Humblet <pierre.humblet@ieee.org>
+
+        * localtime.cc (tzsetwall): Set lcl_is_set and lcl_TZname
+        in the Cygwin specific part of the routine.
+
 2002-12-19  Pierre Humblet <pierre.humblet@ieee.org>
 
         * fhandler.cc (fhandler_base::open): Use "flags" rather than "mode"
diff --git a/winsup/cygwin/localtime.cc b/winsup/cygwin/localtime.cc
index 3000eaffd..3e74667fe 100644
--- a/winsup/cygwin/localtime.cc
+++ b/winsup/cygwin/localtime.cc
@@ -1451,7 +1451,9 @@ tzsetwall P((void))
 	    /* printf("TZ deduced as `%s'\n", buf); */
 	    if (tzparse(buf, lclptr, FALSE) == 0) {
 		settzname();
-		setenv("TZ", buf, 1);
+		lcl_is_set = 1;
+		strlcpy(lcl_TZname, buf, sizeof (lcl_TZname));
+		setenv("TZ", lcl_TZname, 1);
 		return;
 	    }
 	}