Just throwing this out there to see if anyone else experienced this last evening. At 8:00 PM EST last night I had an issue with a number of Exchange servers where the body of new messages could not be displayed in either Outlook, OWA or Blackberry's and a number of users reported other odd behaviors such as items not showing in sent items and Blackberry's showing duplicates of sent messages.
A system reboot seemed to resolve the issue and there are no indications of a problem in the event logs. It didn't happen to every Exchange server though and the only common denominators between the affected systems that I can see is that they all have Ninja Email Security and Vipre Enterprise management installed (no agent). Weird that they all went down at the same time with the same symptoms.