diff -ruN --exclude=obj.* --exclude=*.orig sendmail-8.12.0.Beta10.orig/sendmail/deliver.c sendmail-8.12.0.Beta10/sendmail/deliver.c
--- sendmail-8.12.0.Beta10.orig/sendmail/deliver.c	Wed May 23 04:14:36 2001
+++ sendmail-8.12.0.Beta10/sendmail/deliver.c	Fri Jun 15 02:01:28 2001
@@ -1672,6 +1672,39 @@
 	*pvp++ = NULL;
 
 	/*
+	**  This is the place add an Envelope-To header, if the
+	**  option was set and we're delivering locally.
+	**/
+	if (EnvToHeader) {
+
+		HDR *h;
+
+		/* Clear header if already present */
+		for(h = e->e_header; h != NULL; h = h->h_link) {
+			if (strcasecmp(h->h_field, EnvToHeader) != 0)
+				continue;
+			clrbitmap(h->h_mflags);
+			h->h_flags |= H_ACHECK;
+		}
+	}
+	if (EnvToHeader && bitnset(M_LOCALMAILER, m->m_flags) &&
+	    !bitnset(M_MUSER, m->m_flags)) {
+
+		extern void getenvto __P((ADDRESS *, char ***, int));
+		extern void makeheader __P((char *, char **, char **));
+		char **envto;
+		char *s = NULL;
+
+		/* Now construct new header */
+		getenvto(tochain, &envto, 0);
+		makeheader(EnvToHeader, envto, &s);
+
+		addheader(EnvToHeader, s ? s : "UNKNOWN", 0, &e->e_header);
+		if (s) free(s);
+		free(envto);
+	}
+
+	/*
 	**  Call the mailer.
 	**	The argument vector gets built, pipes
 	**	are created as necessary, and we fork & exec as
diff -ruN --exclude=obj.* --exclude=*.orig sendmail-8.12.0.Beta10.orig/sendmail/headers.c sendmail-8.12.0.Beta10/sendmail/headers.c
--- sendmail-8.12.0.Beta10.orig/sendmail/headers.c	Thu May 10 03:16:10 2001
+++ sendmail-8.12.0.Beta10/sendmail/headers.c	Fri Jun 15 02:01:28 2001
@@ -1898,3 +1898,68 @@
 	}
 	return retlen;
 }
+
+/*
+**  MAKEHEADER -- create a multiline header
+**
+**	Parameters:
+**		h -- initial headername
+**		p -- array of pointers to addresses
+**		s -- pointer to put new data in
+**
+**	Side effects:
+**		removes <> from addresses
+**
+**	Returns:
+**		void
+*/
+void
+makeheader(h, p, s)
+	char *h;
+	char **p;
+	char **s;
+{
+	char *a;
+	int len, alen, slen;
+	int sz;
+	int donl;
+
+	*s = NULL;
+	if (*p == NULL) return;
+
+	len = strlen(h) + 2;
+
+	while((a = *p++) != NULL) {
+		
+		alen = strlen(a);
+		if (*a == '<') {
+			a++;
+			alen -= 2;
+		}
+
+		slen = *s ? strlen(*s) : 0;
+		sz = slen + alen + 1 + (slen ? 1 : 0);
+
+		donl = 0;
+		if (len + alen > 75 && slen > 0) {
+			donl = 1;
+			sz += 2;
+		}
+		*s = realloc(*s, sz);
+		if (*s == NULL) {
+			syserr("!Out of memory!!");
+			/* exit(EX_UNAVAILABLE); */
+		}
+		if (slen == 0)
+			(*s)[0] = 0;
+		else
+			strcat(*s, ",");
+		if (donl) {
+			strcat(*s, "\n\t");
+			len = 8;
+		}
+		strncat(*s, a, alen);
+		(*s)[sz - 1] = 0;
+		len += alen + 1;
+	}
+}
diff -ruN --exclude=obj.* --exclude=*.orig sendmail-8.12.0.Beta10.orig/sendmail/queue.c sendmail-8.12.0.Beta10/sendmail/queue.c
--- sendmail-8.12.0.Beta10.orig/sendmail/queue.c	Fri Jun 15 01:57:39 2001
+++ sendmail-8.12.0.Beta10/sendmail/queue.c	Fri Jun 15 02:03:58 2001
@@ -303,6 +303,9 @@
 	char tf[MAXPATHLEN];
 	char dfname[MAXPATHLEN];
 	char buf[MAXLINE];
+	char **addr_ptr, **ptr;
+	extern void getenvto __P((ADDRESS *, char ***, int));
+
 
 	/*
 	**  Create control file.
@@ -622,6 +625,11 @@
 							false));
 
 		printctladdr(q, tfp);
+		getenvto(q, &addr_ptr, 0);
+		ptr = addr_ptr;
+		while (*ptr)
+			fprintf(tfp, "Y%s\n", *ptr++);
+		free(addr_ptr);
 		if (q->q_orcpt != NULL)
 			(void) sm_io_fprintf(tfp, SM_TIME_DEFAULT, "Q%s\n",
 					     denlstring(q->q_orcpt, true,
@@ -3426,6 +3434,8 @@
 {
 	register SM_FILE_T *qfp;
 	ADDRESS *ctladdr;
+	ADDRESS *addr;
+	ADDRESS *envto = NULL;
 	struct stat st, stf;
 	char *bp;
 	int qfver = 0;
@@ -3837,6 +3847,14 @@
 			orcpt = sm_rpool_strdup_x(e->e_rpool, &bp[1]);
 			break;
 
+		  case 'Y':		/* original envelope-to */
+			addr = setctluser(&bp[1], qfver);
+			addr->q_dups = envto;
+			addr->q_flags |= (QENVTO|QS_DONTSEND);
+			addr->q_flags &= ~(QPRIMARY);
+			envto = addr;
+			break;
+
 		  case 'R':		/* specify recipient */
 			p = bp;
 			qflags = 0;
@@ -3883,14 +3901,20 @@
 				      true);
 			if (q != NULL)
 			{
-				q->q_alias = ctladdr;
+				if (envto) {
+					q->q_alias = envto;
+					envto->q_alias = ctladdr;
+				} else
+					q->q_alias = ctladdr;
 				if (qfver >= 1)
 					q->q_flags &= ~Q_PINGFLAGS;
 				q->q_flags |= qflags;
 				q->q_orcpt = orcpt;
 				(void) recipient(q, &e->e_sendqueue, 0, e);
+				if (envto) q->q_flags &= ~(QENVTO);
 			}
 			orcpt = NULL;
+			envto = NULL;
 			break;
 
 		  case 'S':		/* sender */
diff -ruN --exclude=obj.* --exclude=*.orig sendmail-8.12.0.Beta10.orig/sendmail/readcf.c sendmail-8.12.0.Beta10/sendmail/readcf.c
--- sendmail-8.12.0.Beta10.orig/sendmail/readcf.c	Thu May 24 05:28:32 2001
+++ sendmail-8.12.0.Beta10/sendmail/readcf.c	Fri Jun 15 02:07:50 2001
@@ -2037,6 +2037,10 @@
 # define O_SOFTBOUNCE	0xd0
 	{ "SoftBounce",	O_SOFTBOUNCE,	OI_NONE	},
 #endif /* _FFR_SOFT_BOUNCE */
+#define O_ETRNPROG	0xd1
+	{ "EtrnProg",			O_ETRNPROG,	OI_NONE },
+#define O_ENVTOHEADER	0xd2
+	{ "EnvelopeToHeader",		O_ENVTOHEADER,	OI_NONE },
 	{ NULL,				'\0',		OI_NONE	}
 };
 
@@ -3428,6 +3432,16 @@
 		SoftBounce = atobool(val);
 		break;
 #endif /* _FFR_SOFT_BOUNCE */
+
+	  case O_ETRNPROG:
+		if (EtrnProg) free(EtrnProg);
+		EtrnProg = newstr(val);
+		break;
+  
+	  case O_ENVTOHEADER:
+		if (EnvToHeader) free(EnvToHeader);
+		EnvToHeader = newstr(val);
+		break;
 
 	  default:
 		if (tTd(37, 1))
diff -ruN --exclude=obj.* --exclude=*.orig sendmail-8.12.0.Beta10.orig/sendmail/recipient.c sendmail-8.12.0.Beta10/sendmail/recipient.c
--- sendmail-8.12.0.Beta10.orig/sendmail/recipient.c	Tue May 15 02:02:36 2001
+++ sendmail-8.12.0.Beta10/sendmail/recipient.c	Fri Jun 15 02:11:41 2001
@@ -135,7 +135,82 @@
 		return ret;
 }
 
-/*
+
+/*
+**  GETENVTO -- Walk up the q_alias tree to find the envelope recipient.
+**
+**	Parameters:
+**		Address and a char ***pointer to envto data.
+**		The char *** pointer is confusing. Example usage:
+**		
+**		char **addr_ptrs;
+**
+**		getenvto(address, &addr_ptrs, 0);
+**
+**	Returns:
+**		The char ***envto pointer contains the recipients.
+**
+**	Side Effects:
+**		None other.
+*/
+
+void
+getenvto(a, envtop, level)
+	ADDRESS *a;
+	char ***envtop;
+	int level;
+{
+	ADDRESS *q;
+	char **envto;
+	char **tmp;
+	int sz;
+
+	/*
+	**  Initialize envtop if needed.
+	**/
+	if (level == 0) {
+		*envtop = (char **)xalloc(sizeof(char **));
+		**envtop = NULL;
+	}
+	envto = *envtop;
+
+	if (level > 10) return; /* Should never happen */
+
+	for (q = a; q; q = q->q_alias) {
+		/*
+		**  Perhaps we need to recurse if we
+		**  have a q_dups pointer.
+		**/
+		if (q->q_dups)
+			getenvto (q->q_dups, &envto, level + 1);
+
+		/*
+		**  If this address is QENVTO flagged, add
+		**  it to the envto string.
+		*/
+		if (q->q_flags & QENVTO) {
+
+			/* Check if already present */
+			for(tmp = envto; *tmp; tmp++)
+				if (strcmp(*tmp, q->q_paddr) == 0)
+					break;
+			if (*tmp) continue;
+
+			/* Extend the array. */
+			sz = tmp - envto;
+			envto = realloc(envto, (sz + 2) * sizeof(char **));
+			if (envto == NULL) {
+				syserr("!Out of memory!!");
+				/* exit(EX_UNAVAILABLE); */
+			}
+			tmp = envto + sz;
+			*tmp++ = q->q_paddr;
+			*tmp = NULL;
+		}
+	}
+	*envtop = envto;
+}
+/*
 **  SENDTOLIST -- Designate a send list.
 **
 **	The parameter is a comma-separated list of people to send to.
@@ -468,8 +543,11 @@
 	e->e_to = new->q_paddr;
 	m = new->q_mailer;
 	errno = 0;
-	if (aliaslevel == 0)
+	if (aliaslevel == 0) {
 		new->q_flags |= QPRIMARY;
+		if (!initialdontsend)
+			a->q_flags |= QENVTO;
+	}
 	if (tTd(26, 1))
 	{
 		sm_dprintf("\nrecipient (%d): ", aliaslevel);
@@ -693,6 +771,14 @@
 					q->q_state = new->q_state;
 					q->q_flags |= new->q_flags;
 				}
+				/*
+				**  If the address gets merged with another
+				**  address because they are the same, still
+				**  keep a pointer to it to track it later.
+				*/
+				new->q_dups = q->q_dups;
+				q->q_dups = new;
+  
 				new = q;
 				goto done;
 			}
diff -ruN --exclude=obj.* --exclude=*.orig sendmail-8.12.0.Beta10.orig/sendmail/sendmail.h sendmail-8.12.0.Beta10/sendmail/sendmail.h
--- sendmail-8.12.0.Beta10.orig/sendmail/sendmail.h	Sun May 20 15:55:04 2001
+++ sendmail-8.12.0.Beta10/sendmail/sendmail.h	Fri Jun 15 02:14:59 2001
@@ -222,6 +222,7 @@
 #if PIPELINING
 	struct address	*q_pchain;	/* chain for pipelining */
 #endif /* PIPELINING */
+	struct address	*q_dups;	/* Pointer to duplicates. */
 	char		*q_orcpt;	/* ORCPT parameter from RCPT TO: line */
 	char		*q_status;	/* status code for DSNs */
 	char		*q_rstatus;	/* remote status message for DSNs */
@@ -255,6 +256,7 @@
 #define QBYTRACE	0x00008000	/* DeliverBy: trace */
 #define QBYNDELAY	0x00010000	/* DeliverBy: notify, delay */
 #define QBYNRELAY	0x00020000	/* DeliverBy: notify, relayed */
+#define QENVTO		0x00100000	/* Original envelope recipient */
 #define QTHISPASS	0x40000000	/* temp: address set this pass */
 #define QRCPTOK		0x80000000	/* recipient() processed address */
 
@@ -2147,6 +2149,8 @@
 EXTERN char	*UnixFromLine;	/* UNIX From_ line (old $l macro) */
 EXTERN char	**ExternalEnviron;	/* saved user (input) environment */
 EXTERN char	**SaveArgv;	/* argument vector for re-execing */
+EXTERN char	*EtrnProg;	/* program to be run on ETRN */
+EXTERN char	*EnvToHeader;	/* name of Envelope-To header */
 EXTERN BITMAP256	DontBlameSendmail;	/* DontBlameSendmail bits */
 EXTERN SM_FILE_T	*InChannel;	/* input connection */
 EXTERN SM_FILE_T	*OutChannel;	/* output connection */
diff -ruN --exclude=obj.* --exclude=*.orig sendmail-8.12.0.Beta10.orig/sendmail/srvrsmtp.c sendmail-8.12.0.Beta10/sendmail/srvrsmtp.c
--- sendmail-8.12.0.Beta10.orig/sendmail/srvrsmtp.c	Fri Jun 15 01:57:39 2001
+++ sendmail-8.12.0.Beta10/sendmail/srvrsmtp.c	Fri Jun 15 02:01:28 2001
@@ -258,6 +258,37 @@
 	}
 
 
+static int
+doetrnprog(e, node)
+	ENVELOPE *e;
+	char *node;
+{
+	pid_t pid;
+	int i, st;
+	char *clientaddr;
+
+	clientaddr = macvalue(macid("{client_addr}", NULL), e);
+
+	(void) blocksignal(SIGCHLD);
+
+	if ((pid = dofork()) < 0) {
+		(void) releasesignal(SIGCHLD);
+		return -1;
+	}
+	if (pid == 0) {
+		if ((pid = dofork()) < 0)
+			exit(1);
+		if (pid > 0) exit(0);
+		for(i = 255; i >= 0; i--)
+			close(i);
+		execl(EtrnProg, EtrnProg, clientaddr, node, NULL);
+		exit(1);
+	}
+	st = waitfor(pid);
+	(void) releasesignal(SIGCHLD);
+	return WEXITSTATUS(st);
+}
+
 void
 smtp(nullserver, d_flags, e)
 	char *volatile nullserver;
@@ -2248,6 +2279,15 @@
 				sm_syslog(LOG_INFO, e->e_id,
 					  "%.100s: ETRN %s", CurSmtpClient,
 					  shortenstring(p, MAXSHORTSTR));
+			
+			if (EtrnProg != NULL) {
+				if (doetrnprog(e, p) != 0) {
+					message("451 ETRN cannot fork");
+					break;
+				}
+				message("250 Queuing for node %s started", p);
+				break;
+			}
 
 			id = p;
 			if (*id == '#')