This is basically my first post and would like to congratulate VMware and all the Zimbra people for this fine, excellent, beautiful piece of software.
My Ubuntu 10.04 64x server is up and running for a day now with zimbra open source edition. Ubuntu is by far the biggest linux distro, it would be nice to see the latest LTS versions always supported by zimbra, like 12.04. Not sure, but it seems in bugzilla that support for 12.04 is not schedule for next zimbra release. haaa it's all about money

The server as latest kernel and all components updated, so far do good, nothing broken that I have noticed.

I'm accustomed to MSExchange, Postfix and Citadel, home and work email servers.
At work we have around 120 email user accounts and are currently using Exchange for 1 year now. We tried to go open source before exchange with ubuntu and citadel. Citadel was up and running (crashing) for 2 moths before we added Exchange. Those 2 months were the worse time of my life and I strongly advise users to avoid this MTA, nothing good about it, not stable, constant crashes, berkleyDB database meltdowns, bad user and administrator web gui, bbs based, no support, basically nothing works as publicized in their website. Before moving to exchange we considered using zimbra, but unfortunately back then the ubuntu supported version was too old, and everything kinda felt ubuntu unsupported...

At home I run postfix as a smarthost and used to have citadel for 2 users. 2 days ago citadel email server stop working and melted the database with the latest "easy update install " yes it was easy alright . Also their ubuntu repositories are constantly affected with bad coding errors and have to be constantly fixed. So, if you are planning on running a serious MTA for professional use citadel is wayyyyy out of question. For home use (1 or 2 email accounts) you may run it if you don't mind loosing all your stuff once in a while. So at home, for the past day and a half I have been using Zimbra.... wow Ôô nice stuff, this could easily replace an exchange server. Love it, thank you guys.

I followed this how-to, thanks LHammonds.
The only issue during installation was with my etc/hosts file, that gave me a ldap error upon first save to configuration, so my bad.