MX records for email alias

[somedea]

I have a Windows 2003 server domain with Exchange 2003 server. I'm posting here rather than in the Exchange 2003 forum because my searching finds a lot more info on my questions here.
We have one domain name, abc123.com, that we've been using for everything except our website, which is abc456.com. We have one ISP for abc123.com, but the website was created by a user and is hosted on a GoDaddy type site. The challenge: Set up a new website on one of our servers, still using the abc456.com name, and add an e-mail alias of abc456.com.
I decided against renaming the entire domain. Even though you're supposed to be able to do it in 2003 server and Exchange, I just don't want to chance it.
I used Recipient services and posts from this site, and I now have the e-mail alias working correctly internally. I can't figure out how to get it working correctly externally.
I went to the GoDaddy site and added some A records for mail.abc456.com and smtp.abc456.com to point to our external mail IP, but mail still doesn't get through. Is it necessary to move all records for abc456.com to the new IP?
Because the old website is still running there and we're not ready to replace it yet.
Also, do I need any records for abc456.com on my internal DNS server? If so, how do I do that without getting abc456.com.abc123.com records? Or is that what I need?

 

[MikeBatters]

If you add the abc456.com exptension to the Recipient Policy in the Exchange System Manasger all you internal users will get that address and be able to receive mail to it.

What ever you have between you border & exchange server will probably need to be told that abc456.com is a valid internal domain too and where to send it to.

Thats the basics but more info would be required on thie whole setup to give a definative answer.

Mike

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