Is anyone using Zimbra in a production environment. I must say I am extremely impressed with what I have tinkered with so far. I am actually in the process of building a new mail server for my company, and was wondering about the scalability of Zimbra. I know all the underlying components of Zimbra scale perfectly fine, Postfix, Ldap, Cyrus, etc. but as a whole is Zimbra going to run ok on a Dual Opteron with 2gigs of RAM, SCSI RAID. I am only supporting about 300 or so users, but our current mail server sees about 10K messages a day.

Also I have yet to get Zimbra running correctly on RHEL4 x86_64, I guess I will have to build from source and see how that goes. Is there going to be an easy upgrade path when newer versions are released?

Keep up the great work.