We are starting to evaluate Zimbra Open Source as an archival system for Exchange.

I'll take a user's mailbox and generate a PST file that contains every message in every folder that's over a 1MB and it's more than a year old. For one of our power users, it generated a 4GB PST file.

I made the registry changes to remove the 10MB attachment limit. I started the import and waited, and waited. And waited over Thanksgiving holiday.

96 hours to import a single 4.5GB PST using the import tool! Plus, I didn't set the error threshold registry tweak, so now I have to do it again (it got to about 95% complete).

Does this sound reasonable? I'm running the import wizard on basically a virgin XP installation (it has Outlook 2003 of course) on a fast 2.4ghz Core2Duo w/4GB of memory. The Zimbra server itself isn't a speed demon but it's a 1.6ghz G5 w/2GB of memory.

Any ideas on what the slowdown could be?