Can I have two "main" domains on ISPConfig 3 and use different SSL for each?

I will explain what i want:
I have the "main" domain on my server, example.com, and everything is working flawlessly. I also have few others domains, example2.com, example3.com, example4.com, installed on this sever. To access emails for the second domains over SSL I use mail.example.com (main domain) as mail server and all works fine.

A client of mine wants to host his web host with us and he wants to provide his clients the ability to access their emails at mail.newdomain.com over SSL. I know i can add a domain and setup a SSL for it under website but my question is: won't my server read the root SSL? The main domain example.com SSL? Also, for theis new "main" domain, can I setup ns1.newdomain.com and ns2.newdomain.com so my customer can give that to their clients istead of ns1.example.com? If yes to all of these questions, how do I do that? How do i need to setup the dns zone for the newdomain.com?

Sorry about the noob questions.

Thank you,
Igor

 

Your client needs a own IP. POstfix does not support SNI.

 

Thanks Florian. Can you tell me what I need to do when I assign a new ip to him!? Like what should I do on the DNS zone and postfix?

Thank you,

 

You need an additional server for smtp/submission/smtps for postfix (look at the master.cf and read http://www.postfix.org/master.5.html) and override the relevant settings with " -o <value>"
You may have to adjust dovecot, too.

 

OK. So it probably would be safer to just put the new guy into a new guest and move on, eh?
Thank you.