diff --git a/core/dovecot/conf/dovecot.conf b/core/dovecot/conf/dovecot.conf
index b7cca76c..f4181e0c 100644
--- a/core/dovecot/conf/dovecot.conf
+++ b/core/dovecot/conf/dovecot.conf
@@ -84,6 +84,7 @@ service auth-worker {
 ###############
 protocol imap {
   mail_plugins = $mail_plugins imap_quota imap_sieve
+  mail_max_userip_connections = 20
 }
 
 protocol pop3 {