diff --git a/core/dovecot/conf/dovecot.conf b/core/dovecot/conf/dovecot.conf
index f501a5f9..15d6ed72 100644
--- a/core/dovecot/conf/dovecot.conf
+++ b/core/dovecot/conf/dovecot.conf
@@ -173,6 +173,9 @@ plugin {
   # Include the recipient in vacation replies so that DKIM applies
   sieve_vacation_send_from_recipient = yes
 
+  # Use To: header from original message becaus envelope has a SRS address
+  sieve_vacation_to_header_ignore_envelope = yes
+
   # extract spam score from headers
   sieve_spamtest_status_type = strlen
   sieve_spamtest_status_header = X-Spam-Level