diff --git a/.env.example b/.env.example
index ea6270e..63d19ec 100644
--- a/.env.example
+++ b/.env.example
@@ -24,11 +24,10 @@ STALWART_RECOVERY_ADMIN=
 ROUNDCUBE_BIND=127.0.0.1
 ROUNDCUBE_PORT=8091
 
-# Optional IMAP endpoint for Roundcube. Set an IP address here when DNS for
-# MAIL_HOSTNAME is unavailable from the Roundcube container.
-# ROUNDCUBE_IMAP_HOST=192.0.2.10
-# Optional SMTP submission endpoint for Roundcube. Defaults to MAIL_HOSTNAME.
-# ROUNDCUBE_SMTP_HOST=192.0.2.10
+# Roundcube IMAP and SMTP endpoints. Replace either value with a Stalwart IP
+# address when MAIL_HOSTNAME is unavailable from the Roundcube container.
+ROUNDCUBE_IMAP_HOST=${MAIL_HOSTNAME}
+ROUNDCUBE_SMTP_HOST=${MAIL_HOSTNAME}
 
 # Roundcube database
 RC_DB_NAME=roundcube