diff -r -u zmailer-2.99.18/libsh/regex.c zmailer-2.99.18-IRIX53/libsh/regex.c
--- zmailer-2.99.18/libsh/regex.c	Sun Mar 26 17:06:12 1995
+++ zmailer-2.99.18-IRIX53/libsh/regex.c	Tue Oct 10 16:38:04 1995
@@ -72,6 +72,9 @@
 char *realloc ();
 #endif
 
+#ifdef	FOR_IRIX_5_3
+#include <alloca.h>
+#endif
 
 /* Define the syntax stuff for \<, \>, etc.  */
 
diff -r -u zmailer-2.99.18/router/prototypes.h zmailer-2.99.18-IRIX53/router/prototypes.h
--- zmailer-2.99.18/router/prototypes.h	Fri Aug 25 14:26:30 1995
+++ zmailer-2.99.18-IRIX53/router/prototypes.h	Tue Oct 10 16:15:38 1995
@@ -59,7 +59,7 @@
 extern void	sb_external();
 extern void	v_set();
 extern void	v_setl();
-#ifndef	tolower
+#if	!defined(tolower) && !defined(sgi)
 extern int	tolower __((const int));
 #endif
 
diff -r -u zmailer-2.99.18/scheduler/mailq.c zmailer-2.99.18-IRIX53/scheduler/mailq.c
--- zmailer-2.99.18/scheduler/mailq.c	Mon Aug 21 15:49:15 1995
+++ zmailer-2.99.18-IRIX53/scheduler/mailq.c	Tue Oct 10 16:44:48 1995
@@ -26,7 +26,10 @@
 #endif	/* USE_INET */
 
 #ifdef sgi
+/* Flock is in and working with 5.3 ? **/
+#ifndef	FOR_IRIX_5_3
 flock() { return 0; }
+#endif
 #endif
 
 #ifdef	MALLOC_TRACE
diff -r -u zmailer-2.99.18/scheduler-new/mailq.c zmailer-2.99.18-IRIX53/scheduler-new/mailq.c
--- zmailer-2.99.18/scheduler-new/mailq.c	Wed Oct  4 12:33:38 1995
+++ zmailer-2.99.18-IRIX53/scheduler-new/mailq.c	Tue Oct 10 16:45:16 1995
@@ -30,7 +30,10 @@
 #endif	/* USE_INET */
 
 #ifdef sgi
+/* Flock is in and working with 5.3 ? **/
+#ifndef	FOR_IRIX_5_3
 flock() { return 0; }
+#endif
 #endif
 
 #ifdef	MALLOC_TRACE
