Can I upgrade from FOSS to NE ?

[spectra]

Hey Gang,
I only know how to install and run the open source version of zimbra using dns setup as discussed here Ubuntu 8.04 LTS Server (Hardy Heron) Install Guide - Zimbra :: Wiki

I then have zimbra relay mail using another email server.
Zimbra receives email because I forward a copy from the main actual server to zimbra.

This works well. So well that the boss now wants to buy Network version so we can run 64-bit on Ubuntu 10.04.1

Questions?

1. If I go thru with setup as I know how with FOSS on 64 bit Ubuntu 10.04.1, can I then upgrade to NE on my same 10.04.1. Note Ubuntu 10.04.1 LTS under FOSS is beta. Under NE it's not beta. Will I be ok with my install approach ?

2. My boss wants to have one zimbra instance service 2 domains that he has. I guess I will see in the NE version how to setup that separation ?

3. The NE version can be setup, as I mentioned before, as a relay ? That's the only way I know to setup and run zimbra. We don't mind because we want to have a backup of the emails anyway on the main server.


TIA for all comments and help