http://www.zimbra.com/forums/install...html#post578561) Should I add domain1.com as another domain?
http://www.zimbra.com/forums/install...html#post578562) Should I make users under @domain1.com or @mail.domain1.com
Yes/No. These are forwarded internally, ie when you click "Junk", they get forwarded to that account. You only need one set per server. . not domain.3) Will the spam accounts and admin accounts work ok when they are email@example.com? Or should I give them aliases at @domain1.com?
no. http://www.zimbra.com/forums/install...html#post578564) Do I need to create @mail.domain2.com even if I make the users under @domain2.com?
No. See question # 3. Junk accounts are for the server to learn. Once forwarded, the server takes care of the rest.5) Do I need to create spam accounts for these as well?