mgb
I get 1 ip only for domain
sme server can host many domains on 1 external IP.
Additional domains are called virtual domains, add them in the server manager Domains panel.
External DNS records will point many domain names at the same external sme IP.
SME server can correctly resolve many domains if you add them to the Domains panel.
I do not understand the rest of what you said in your last post.
You need to do better English translation.
From your earlier posts, my understanding of what you want to do, is to have email addressed to certain users, to be processed by the exchange server.
There are probably a few ways this could be achieved, I believe I have suggested two ways.
One way is to send mail to those users at a different domain, and sme is configured to delegate that whole domain (domain2), to the exchange server. This should work.
The other way is to configure your exchange server to have a valid and resolvable domain name (eg domain2), you can then forward email to a valid email address for the exchange server eg sme user17 forwards to exchange user17@domain2