diff --git a/ChangeLog b/ChangeLog
index 56b4af7c4..7cdcbf091 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+20060903
+ - (dtucker) [configure.ac openbsd-compat/openbsd-compat.h] Check for
+   declaration of writev(2) and declare it ourselves if necessary.  Makes
+   the atomiciov() calls build on really old systems.  ok djm@
+
 20060902
  - (dtucker) [openbsd-compat/port-irix.c] Add errno.h, found by Iain Morgan.
  - (dtucker) [ssh-keyscan.c ssh-rand-helper.c ssh.c sshconnect.c
@@ -5385,4 +5390,4 @@
    - (djm) Trim deprecated options from INSTALL. Mention UsePAM
    - (djm) Fix quote handling in sftp; Patch from admorten AT umich.edu
 
-$Id: ChangeLog,v 1.4527 2006/09/02 05:32:40 dtucker Exp $
+$Id: ChangeLog,v 1.4528 2006/09/03 12:44:49 dtucker Exp $
diff --git a/configure.ac b/configure.ac
index c37d7f499..cdabbd8a1 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,4 +1,4 @@
-# $Id: configure.ac,v 1.357 2006/09/01 10:29:11 dtucker Exp $
+# $Id: configure.ac,v 1.358 2006/09/03 12:44:49 dtucker Exp $
 #
 # Copyright (c) 1999-2004 Damien Miller
 #
@@ -15,7 +15,7 @@
 # OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 
 AC_INIT(OpenSSH, Portable, openssh-unix-dev@mindrot.org)
-AC_REVISION($Revision: 1.357 $)
+AC_REVISION($Revision: 1.358 $)
 AC_CONFIG_SRCDIR([ssh.c])
 
 AC_CONFIG_HEADER(config.h)
@@ -1328,6 +1328,12 @@ AC_CHECK_DECLS(O_NONBLOCK, , ,
 #endif
 	])
 
+AC_CHECK_DECLS(writev, , , [
+#include <sys/types.h>
+#include <sys/uio.h>
+#include <unistd.h>
+	])
+
 AC_CHECK_FUNCS(setresuid, [
 	dnl Some platorms have setresuid that isn't implemented, test for this
 	AC_MSG_CHECKING(if setresuid seems to work)
diff --git a/openbsd-compat/openbsd-compat.h b/openbsd-compat/openbsd-compat.h
index 278ac71d9..aac2e6cbc 100644
--- a/openbsd-compat/openbsd-compat.h
+++ b/openbsd-compat/openbsd-compat.h
@@ -1,4 +1,4 @@
-/* $Id: openbsd-compat.h,v 1.41 2006/08/30 17:24:42 djm Exp $ */
+/* $Id: openbsd-compat.h,v 1.42 2006/09/03 12:44:50 dtucker Exp $ */
 
 /*
  * Copyright (c) 1999-2003 Damien Miller.  All rights reserved.
@@ -131,6 +131,11 @@ int getgrouplist(const char *, gid_t, gid_t *, int *);
 int BSDgetopt(int argc, char * const *argv, const char *opts);
 #endif
 
+#if defined(HAVE_DECL_WRITEV) && HAVE_DECL_WRITEV == 0
+# include <sys/types.h>
+# include <sys/uio.h>
+int writev(int, struct iovec *, int);
+#endif
 
 /* Home grown routines */
 #include "bsd-misc.h"