diff --git a/Build.sh b/Build.sh
index 856428b..2b97301 100644
--- a/Build.sh
+++ b/Build.sh
@@ -1,5 +1,5 @@
 #!/bin/sh
-srcversion='$MirOS: src/bin/mksh/Build.sh,v 1.518 2012/03/27 22:36:48 tg Exp $'
+srcversion='$MirOS: src/bin/mksh/Build.sh,v 1.519 2012/03/27 22:41:16 tg Exp $'
 #-
 # Copyright (c) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
 #		2011, 2012
@@ -1335,7 +1335,7 @@ else
 		#define EXTERN
 		#define MKSH_INCLUDES_ONLY
 		#include "sh.h"
-		__RCSID("$MirOS: src/bin/mksh/Build.sh,v 1.518 2012/03/27 22:36:48 tg Exp $");
+		__RCSID("$MirOS: src/bin/mksh/Build.sh,v 1.519 2012/03/27 22:41:16 tg Exp $");
 		int main(void) { printf("Hello, World!\n"); return (0); }
 EOF
 	case $cm in
@@ -1401,11 +1401,13 @@ EOF
 #
 ac_test flock <<-'EOF'
 	#include <fcntl.h>
+	#undef flock
 	int main(void) { return (flock(0, LOCK_EX | LOCK_UN)); }
 EOF
 
 ac_test lock_fcntl '!' flock 1 'whether we can lock files with fcntl' <<-'EOF'
 	#include <fcntl.h>
+	#undef flock
 	int main(void) {
 		struct flock lks;
 		lks.l_type = F_WRLCK | F_UNLCK;
diff --git a/sh.h b/sh.h
index 8ad6de4..af3c606 100644
--- a/sh.h
+++ b/sh.h
@@ -152,7 +152,7 @@
 #endif
 
 #ifdef EXTERN
-__RCSID("$MirOS: src/bin/mksh/sh.h,v 1.531 2012/03/27 22:36:53 tg Exp $");
+__RCSID("$MirOS: src/bin/mksh/sh.h,v 1.532 2012/03/27 22:41:17 tg Exp $");
 #endif
 #define MKSH_VERSION "R40 2012/03/27"
 
@@ -204,6 +204,12 @@ typedef unsigned long rlim_t;
 typedef void (*sig_t)(int);
 #endif
 
+/* un-do vendor damage */
+
+#undef BAD		/* AIX defines that somewhere */
+#undef flock		/* SCO UnixWare defines that to flock64 but ENOENT */
+
+
 #ifndef MKSH_INCLUDES_ONLY
 
 /* extra types */
@@ -296,7 +302,6 @@ struct rusage {
 #endif
 #endif
 
-#undef BAD		/* AIX defines that somewhere */
 
 /* OS-dependent additions (functions, variables, by OS) */