--- rcs-5.7/man/co.1.orig	2003-10-24 13:56:53.000000000 -0400
+++ rcs-5.7/man/co.1	2003-10-24 13:59:22.000000000 -0400
@@ -324,6 +324,10 @@
 retrieves the latest revision on the selected branch whose state is set to
 .IR state .
 .TP
+.BI \-S
+Turns on same user locks.  When this is enabled the user cannot check out
+the same file twice.
+.TP
 .B \-T
 Preserve the modification time on the \*r file
 even if the \*r file changes because a lock is added or removed.
--- rcs-5.7/src/rcsedit.c.orig	2003-10-24 12:34:57.000000000 -0400
+++ rcs-5.7/src/rcsedit.c	2003-10-24 13:51:14.000000000 -0400
@@ -1708,9 +1708,10 @@
 }
 
 	int
-addlock(delta, verbose)
+addlock(delta, verbose, sameuserlocks)
 	struct hshentry * delta;
 	int verbose;
+	int sameuserlocks;
 /*
  * Add a lock held by caller to DELTA and yield 1 if successful.
  * Print an error message if verbose and yield -1 if no lock is added because
@@ -1722,9 +1723,10 @@
 
 	for (next = Locks;  next;  next = next->nextlock)
 		if (cmpnum(delta->num, next->delta->num) == 0)
-			if (strcmp(getcaller(), next->login) == 0)
+			if (strcmp(getcaller(), next->login) == 0 && !sameuserlocks)
 				return 0;
-			else {
+			else { 
+		
 				if (verbose)
 				  rcserror("Revision %s is already locked by %s.",
 					delta->num, next->login
--- rcs-5.7/src/ci.c.orig	2003-10-24 12:53:05.000000000 -0400
+++ rcs-5.7/src/ci.c	2003-10-24 13:50:36.000000000 -0400
@@ -566,7 +566,7 @@
 	}
 
 
-	if (lockflag  &&  addlock(&newdelta, true) < 0) continue;
+	if (lockflag  &&  addlock(&newdelta, true, false) < 0) continue;
 
 	if (keepflag && *prevname.string)
 	    if (addsymbol(newdelta.num, prevname.string, false)  <  0)
--- rcs-5.7/src/rcsbase.h.orig	2003-10-24 12:55:50.000000000 -0400
+++ rcs-5.7/src/rcsbase.h	2003-10-24 12:56:06.000000000 -0400
@@ -454,7 +454,7 @@
 RILE *rcswriteopen P((struct buf*,struct stat*,int));
 char const *makedirtemp P((int));
 char const *getcaller P((void));
-int addlock P((struct hshentry*,int));
+int addlock P((struct hshentry*,int,int));
 int addsymbol P((char const*,char const*,int));
 int checkaccesslist P((void));
 int chnamemod P((FILE**,char const*,char const*,int,mode_t,time_t));
--- rcs-5.7/src/co.c.orig	2003-10-24 13:20:49.000000000 -0400
+++ rcs-5.7/src/co.c	2003-10-24 13:49:20.000000000 -0400
@@ -203,6 +203,7 @@
 	int changelock;  /* 1 if a lock has been changed, -1 if error */
 	int expmode, r, tostdout, workstatstat;
 	int Ttimeflag;
+	int sameuserlocks;
 	struct buf numericrev;	/* expanded revision number	*/
 	char finaldate[datesize];
 #	if OPEN_O_BINARY
@@ -217,6 +218,7 @@
 	suffixes = X_DEFAULT;
 	tostdout = false;
 	Ttimeflag = false;
+	sameuserlocks = false;	
 
 	argc = getRCSINIT(argc, argv, &newargv);
 	argv = newargv;
@@ -286,12 +288,20 @@
                         }
                         break;
 
+		case 'S':
+			/* 
+			 *  Enable strict locks (i.e. even the same user cannot
+ 			 *  re-check out a file with a lock that he owns.
+			 */
+			sameuserlocks = true;
+			break;
+ 
 		case 'T':
 			if (*a)
 				goto unknown;
 			Ttimeflag = true;
 			break;
-
+		
                 case 'w':
 			if (author) redefined('w');
 			if (*a)
@@ -417,7 +427,7 @@
 			: lockflag == 0 ?
 				0
 			:
-				addlock(targetdelta, true);
+				addlock(targetdelta, true, sameuserlocks);
 
 		if (
 			changelock < 0
--- rcs-5.7/src/rcs.c.orig	2003-10-24 13:51:39.000000000 -0400
+++ rcs-5.7/src/rcs.c	2003-10-24 13:53:39.000000000 -0400
@@ -1437,8 +1437,8 @@
 			numrev.string
 		    );
 	       else {
-		    if ((r = addlock(target, false)) < 0  &&  breaklock(target))
-			r = addlock(target, true);
+		    if ((r = addlock(target, false, false)) < 0  &&  breaklock(target))
+			r = addlock(target, true, false);
 		    if (0 <= r) {
 			if (r)
 			    diagnose("%s locked\n", target->num);