Zimbra

https://www.zimbra.com/downloads/zimbra-collaboration-open-source

apt-get install libgmp10 libperl5.18 unzip pax sysstat sqlite3 dnsmasq wget libaio1
nano /etc/hostname

set

mail.host-name.localdomain

then

nano /etc/hosts

add

ip.add.res.ss mail.host-name.localdomain mail

then

nano /etc/dnsmasq.conf

then

server=192.168.1.101
domain=sendaljepit.local
mx-host=sendaljepit.local, mail.sendaljepit.local, 5
#repeat mx-host=mail.sendaljepit.local, mail.sendaljepit.local, 5
#why? listen-address=127.0.0.1

Also this guy explains the repeat lines: http://forums.zextras.com/zimbra-howto/485-setting-up-dnsmasq-instead-bind-bulletproof-internal-dns-resolution-splitdns.html

i also changed this line to my liking

address=/mail.domain.com/192.168.0.2