Continually getting 502 Error: command not implemented - any thoughts?

[skhoury]

Hello all,

Ok first let me place my disclaimer: this is my first time configuring/using postfix!

here is the scenario: I built a postfix server and placed it infront of my Exchange server.

So far, I've got the postfix server to simply forward all mail to the exchange server...this part works.

If I telnet to the postfix box from the local network or directly on the box itself (localhost), then it works.

However - here is the problem:

I gave the postfix box one of my free IPs so I can test it prior to going live. When I telnet to the box across the internet, Postfix picks up the connection with the following:

"220 ******************************"
(Please note that I didnt place those asteriks there...It just comes up that way for some reason....but if I telnet locally it comes up with the correct host name, etc.)

Then if I type this to start the message process:
HELO foo.com

I get this:
502 Error: command not implemented

this is the error message I get no matter what command I pass to the server - even HELP.

Does anyone know what I may have done wrong? Perhaps I just have the command syntax wrong? But then why would it work locally....

Many thanks in advance!!!

Sam