Although I have installed zimbra locally.. but need to clarify about few things in zimbra :-
1) Is it fine to deploy Open source edition of zimbra for "n" number of users? Any limitations ?
2) Is zimbra providing us antispam and antivirus feature for mailings?
3) After installing zimbra, it's antivirus will fetch latest updates from the server?
4) Do we need to enable antispam/antivirus feature in it OR it's already enabled?
5) Can we make an entry for Domainhostkeys for authentication with yahoo?
I have other solutions also like postfix with virtual users and domains but zimbra's suite is attractive so just need to confirm it.