Apply by doing:
	cd /usr/src
	patch -p0 < 010_sendmail3.patch

And then rebuild and install sendmail:
	cd gnu/usr.sbin/sendmail
	make obj
	make depend
	make
	make install

Index: gnu/usr.sbin/sendmail/sendmail/main.c
===================================================================
RCS file: /cvs/src/gnu/usr.sbin/sendmail/sendmail/main.c,v
retrieving revision 1.21
retrieving revision 1.21.6.1
diff -u -p -r1.21 -r1.21.6.1
--- gnu/usr.sbin/sendmail/sendmail/main.c	24 Jun 2004 03:59:27 -0000	1.21
+++ gnu/usr.sbin/sendmail/sendmail/main.c	8 Aug 2006 20:33:12 -0000	1.21.6.1
@@ -2893,6 +2893,7 @@ finis(drop, cleanup, exitstat)
 				dropenvelope(CurEnv, true, false);
 				sm_rpool_free(CurEnv->e_rpool);
 				CurEnv->e_rpool = NULL;
+				CurEnv->e_to = NULL;
 			}
 			else
 				poststats(StatFile);