Apply by doing:
	cd /usr/src
	patch -p0 < 011_pppd.patch

And then rebuild and install pppd:
	cd usr.sbin/pppd
	make obj cleandir depend
	make && make install

Index: usr.sbin/pppd/main.c
===================================================================
RCS file: /cvs/src/usr.sbin/pppd/main.c,v
retrieving revision 1.31
retrieving revision 1.31.2.1
diff -u -r1.31 -r1.31.2.1
--- usr.sbin/pppd/main.c	15 May 2001 19:56:06 -0000	1.31
+++ usr.sbin/pppd/main.c	30 Jul 2002 07:29:13 -0000	1.31.2.1
@@ -797,7 +797,7 @@
     restore_tty(ttyfd);
 
     if (tty_mode != (mode_t) -1)
-	chmod(devnam, tty_mode);
+	fchmod(ttyfd, tty_mode);
 
     close(ttyfd);
     ttyfd = -1;