diff --git a/debian/postinst b/debian/postinst
index b416b7e8..9ab78798 100644
--- a/debian/postinst
+++ b/debian/postinst
@@ -14,6 +14,13 @@ case "$1" in
 		_dh_action=start
 	fi
 	deb-systemd-invoke $_dh_action proxmox-backup.service proxmox-backup-proxy.service >/dev/null || true
+
+	if test -n "$2"; then
+		if dpkg --compare-versions "$2" 'le' '0.8.10-1'; then
+			echo "Fixing up termproxy user id in task log..."
+			flock -w 30 /var/log/proxmox-backup/tasks/active.lock sed -i 's/:termproxy::root: /:termproxy::root@pam: /' /var/log/proxmox-backup/tasks/active
+		fi
+	fi
     ;;
 
     abort-upgrade|abort-remove|abort-deconfigure)