diff --git a/rootfs/etc/confd/templates/90-sieve.conf.tmpl b/rootfs/etc/confd/templates/90-sieve.conf.tmpl
index 1901943..1ccf72e 100644
--- a/rootfs/etc/confd/templates/90-sieve.conf.tmpl
+++ b/rootfs/etc/confd/templates/90-sieve.conf.tmpl
@@ -1,3 +1,7 @@
+protocol managesieve {
+  disable_plaintext_auth = no
+}
+
 plugin {
   sieve = file:~/sieve;active=~/.dovecot.sieve
   sieve_after = /var/lib/vmail/sieve-after/