diff --git a/gnu/usr.bin/cvs/lib/config.h.proto b/gnu/usr.bin/cvs/lib/config.h.proto
index b88faa7d073..30a4f00e0b6 100644
--- a/gnu/usr.bin/cvs/lib/config.h.proto
+++ b/gnu/usr.bin/cvs/lib/config.h.proto
@@ -324,7 +324,7 @@
 #define HAVE_SYS_STAT_H 1
 
 /* Define to 1 if you have the <sys/timeb.h> header file. */
-#define HAVE_SYS_TIMEB_H 1
+/* #undef HAVE_SYS_TIMEB_H */
 
 /* Define to 1 if you have the <sys/time.h> header file. */
 #define HAVE_SYS_TIME_H 1