With pleasure, I noticed that Ubuntu 8.04 LTS is now supported as well. I currently run 5.0.5 on Ubuntu 6.06 LTS and I would like to move to the latest status on both Zimbra and the OS. What is the recommended way:

a) Upgrade Zimbra 5.0.5 to 5.0.9 (using the 6.06 Zimbra package) and then upgrade Ubuntu to 8.04? Would this require to run 5.0.9 install again using the Ubuntu 8.04 Zimbra 5.0.9 package?

b) Upgrade Ubuntu to 8.04 first and upgrade to Zimbra 5.0.9 afterwards?

c) Forget the upgrade to 8.04 and do a fresh 8.04 instance, installing 5.0.9 from scratch and migrate data to the new instance? What is the procedure to move the data from one server to the other one?

I prefer a solution out of option a) or b). Any recommendations?