Memory useage on 5.0.2 GA
I use 5.0.2 GA on ubuntu 7.10 server, with memory useage seldom above 500 Megs. (only time was actually during install)
Admittedly I am running it for demo purposes and the load isn't especially high, but it is delivering mails and working with Thunderbird with Lightning and zimbra desktop.
I have reduced ram on this box to 768 Megs.
/etc/security/limits.conf on debian systems may help
/etc/sysconfig/limit* (or something like it on RPM distros)
8.x NE + OSS KVM guests and Physical servers Ubuntu 12.04, RHEL 5 + 6 .
on Dell server hardware.
Previously: ZCS OSS and NE 7, 6, 5, 4, 3 variously on physical and virtual