smtp on the AS400

[Jerry Draper <midrangel@xxxxxxxxxxxxx>]

I am not able to send messages with mmail from my as400 to addresses 
outside my company's domain using either Robot or MMAIL.

Any ideas?  It was working fine last week with no changes to either the 
smtp server (ms exchange) or AS400 (supposedly).

Here's my error message when I telnet into my exchange server on port 25:

220 nv1exc101.corp.company.com Microsoft ESMTP MAIL Service, Version: 5.
helo s1048155
250 nv1exc101.corp.company.com Hello [172.16.1.1]
mail from:as400@xxxxxxxxxxx
250 2.1.0 as400@xxxxxxxxxxxxxxxxxxxxx OK
rcpt to:jdraper@xxxxxxxxxxxxx
550 5.7.1 Unable to relay for jdraper@xxxxxxxxxxxxx

I'm pretty sure this is an exchange issue but I have to be sure.

There is no problem sending msgs from outlook thru the same smtp server.

Jerry Draper