I had some concerns earlier this morning and have a better understanding.
Here is my senario. My routing settings in xchange5.5 were to support
relaying (for POP support). The domain was set as "mail sent to" xxx.com
routed to <inbound>. No other restrictions were in place so I used telnet to
send some junk emails. This is not good...
So I fixed this but then my POP clients failed. How can I prevent relaying
but support POP clients who access their Exchange boxes from the field via
the internet? (Using Exchange POP3 feature)