$NetBSD$

--- sendmail/conf.h.orig	2020-05-19 21:54:33.000000000 +0200
+++ sendmail/conf.h	2021-03-18 14:21:34.720788259 +0100
@@ -235,8 +235,12 @@
 #ifndef PIPELINING
 # define PIPELINING	1	/* SMTP PIPELINING */
 #endif
 
+#ifndef NAMED_RESN
+# define NAMED_RESN	1	/* res_n* functions are available */
+#endif
+
 /**********************************************************************
 **  End of site-specific configuration.
 **********************************************************************/
 
