Update 20130925: The newly tuned spam detection system exhibited the same instability as before. We have disabled it.

Email sent last night and this morning should be delivered by mid-afternoon.

Update 20130924: We have worked with Sophos to tune the spam detection system. The new system is now in place and we are monitoring mail system performance.

Update 20130923: Friday’s update has proven unstable. We have reversed the change and are continuing to work with Sophos.

Over the weekend you may have received emails saying that the server “can’t deliver message for 4 hours”. These messages were delivered once Friday’s change was reversed. No email has been lost during this process.
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Update 20130920: We have installed an update to spam detection. Spam detection and prevention is now functioning. We will continue to monitor the system.
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Update 20130918: We have identified a problem with spam detection profile updates. We are working with Sophos, our antispam vendor to resolve the problem.
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We have received reports of increased spam to @emu.edu email addresses. We are investigating the problem.

With our moving to GMail (Jan-Mar 2014), our internal spam control resources will be replaced with Google spam controls.