I am trying to wrap my head around the following config options: # Port 25 or local is MTA IS_MTA_PORT = or{ \ {eq{$interface_port}{25}} \ {eq{$interface_port}{-1}} \ } # advertise SMTP AUTH on all ports except the inbound MTA one, which of course is 25. # Auth on ports not used for MTA (=> MUAs) auth_advertise_hosts = ${if IS_MTA_PORT {}{*}} So our MuAs are set to use port 587 with ASMTP because we are advertising auth on ports other than 25. However, now I'd like to still use TLS encryption, but only as an option: 1. If the MuA is not set to use TLS/SSL, then do not use it 2. If it is set to use TLS/SSL, then use it. The following line requires TLS encryption for all authenticated connections: auth_advertise_hosts = ${if eq{$tls_cipher}{}{}{*}} How do I combine the two auth_advertise_hosts - one with encryption and one without? Both on ports other than 25 (e.g 587 or 465) Or maybe advertise encrypted ASMTP on 465 and unencrypted on 587? Thanks in advance -- Best regards, Odhiambo WASHINGTON, Nairobi,KE +254 7 3200 0004/+254 7 2274 3223 "Oh, the cruft.", egrep -v '^$|^.*#' :-)