Our Mitel vendor is having a problem getting our new Mitel 5000 configured to use our Exchange 2003 SMTP server to forward e-mail to users. Rather than requiring SMTP authentication in our small network, we prefer to lock down the computers and network in general and simply limit SMTP connection and relay to client IP addresses within our local subnets and inbound (McAfee) spam-blocking service. Therefore, SMTP login is not required.
The vendor provided me a log snippet that includes this: "334 VXNlcm5hbWU6"
“VXNlcm5hbWU6” is a response from the SMTP server and is the BASE64-encoded string for “Username”, meaning that the Mitel 5000 is offering to authenticate, so I infer two things:
1. The Mitel 5000 is communicating with the SMTP server.
2. Instead of HELO (which would not allow AUTH requests), the Mitel 5000 is sending EHLO and then AUTH LOGIN, when neither is necessary. But the person doing the setup says there is no option to not require authentication.
Where is the configuration option on the Mitel 5000 to use HELO instead of EHLO and/or to use SMTP without any authentication request? The vendor is a bit protective of his user interface, so I have not seen it myself.
