diff --git a/src/opnsense/scripts/interfaces/ppp-linkdown.sh b/src/opnsense/scripts/interfaces/ppp-linkdown.sh
index fc4fcbff9..0aa4e91da 100755
--- a/src/opnsense/scripts/interfaces/ppp-linkdown.sh
+++ b/src/opnsense/scripts/interfaces/ppp-linkdown.sh
@@ -1,5 +1,7 @@
 #!/bin/sh
 
+export PATH=/bin:/usr/bin:/usr/local/bin:/sbin:/usr/sbin:/usr/local/sbin
+
 IF="${1}"
 AF="${2}"
 IP="${3}"
@@ -52,6 +54,14 @@ elif [ "${AF}" = "inet6" ]; then
 
 	# Do not remove gateway used during filter reload.
 	rm -f /tmp/${IF}_routerv6 /tmp/${IF}upv6 /tmp/${IF}_ipv6
+
+	# flush stale IPv6 addresses since mpd5 will not do it
+	php << EOF
+<?
+require_once 'util.inc';
+require_once 'interfaces.inc';
+interfaces_addresses_flush('${IF}', 6);
+EOF
 fi
 
 daemon -f /usr/local/opnsense/service/configd_ctl.py dns reload