Howdy, all. I just finished a tutorial on configuring a CentOS 5 system for use with the Zimbra groupware system, which provides email, shared calendars, and chat functionality. This may prove useful for those of you who have had MTA-related issues. Zimbra is a pretty powerful solution, and while it's not right for everyone it does offer some nice integrated features.
You can find the tutorial here:
http://www.classhelper.org/articles/cen ... ra-server/
I hope you find it useful.

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