If there is a Turnkey appliance that SHOULD be 64-bit only it's Zimbra. As soon as it is released I will be upgrading. If there's one thing you shouldn't skimp on its your mail server. I wouldn't run Zimbra on anything less than a 4+ core 64-bit processor with 8GB+ of RAM.
No need for 32-bit
If there is a Turnkey appliance that SHOULD be 64-bit only it's Zimbra. As soon as it is released I will be upgrading. If there's one thing you shouldn't skimp on its your mail server. I wouldn't run Zimbra on anything less than a 4+ core 64-bit processor with 8GB+ of RAM.