diff --git a/auth/ldap/lang/en/auth_ldap.php b/auth/ldap/lang/en/auth_ldap.php
index a6e4ff600f43e..7962513b9ca00 100644
--- a/auth/ldap/lang/en/auth_ldap.php
+++ b/auth/ldap/lang/en/auth_ldap.php
@@ -101,7 +101,7 @@
 $string['auth_ntlmsso_enabled_key'] = 'Enable';
 $string['auth_ntlmsso_ie_fastpath'] = 'Set to yes to enable the NTLM SSO fast path (bypasses certain steps and only works if the client\'s browser is MS Internet Explorer).';
 $string['auth_ntlmsso_ie_fastpath_key'] = 'MS IE fast path?';
-$string['auth_ntlmsso_subnet'] = 'If set, it will only attempt SSO with clients in this subnet. Format: xxx.xxx.xxx.xxx/bitmask';
+$string['auth_ntlmsso_subnet'] = 'If set, it will only attempt SSO with clients in this subnet. Format: xxx.xxx.xxx.xxx/bitmask. Separate multiple subnets with \',\' (comma).';
 $string['auth_ntlmsso_subnet_key'] = 'Subnet';
 $string['auth_ntlmsso_type_key'] = 'Authentication type';
 $string['auth_ntlmsso_type'] = 'The authentication method configured in the web server to authenticate the users (if in doubt, choose NTLM)';