Just wanted to let you know, in case any of you plan on installing Zimbra on Ubuntu 8.0.4 64 bit:
There seems to be a severe problem within Zimbra. Java is constantly consuming more memory, it goes from 15% up within a week to 37% and climbs until the server (Zimbra part) crashes (around 60-70%).
Support has been looking into the problem, but they have not come up with a solution. Reducing java_heap to 25% made it a bit better, but memory is still constantly climbing.
Seems to be a memory leak somewhere...
Stay away from this until it is resolved (my opinion)!
I have opened a bug for this: Bug 34040 – Zimbra java consumes all memory on Ubuntu 8.0.4 64bit