diff --git a/htdocs/langs/en_US/admin.lang b/htdocs/langs/en_US/admin.lang
index a4ece445581..e2c39c45a3d 100644
--- a/htdocs/langs/en_US/admin.lang
+++ b/htdocs/langs/en_US/admin.lang
@@ -272,6 +272,7 @@ MAIN_MAIL_EMAIL_FROM=Sender email for automatic emails (By default in php.ini: <
 MAIN_MAIL_ERRORS_TO=Sender email used for error returns emails sent
 MAIN_MAIL_AUTOCOPY_TO= Send systematically a hidden carbon-copy of all sent emails to
 MAIN_DISABLE_ALL_MAILS=Disable all emails sendings (for test purposes or demos)
+MAIN_MAIL_FORCE_SENDTO=Send all emails to (instead of real recipients, for test purposes)
 MAIN_MAIL_SENDMODE=Method to use to send EMails
 MAIN_MAIL_SMTPS_ID=SMTP ID if authentication required
 MAIN_MAIL_SMTPS_PW=SMTP Password if authentication required