I realized that the problem is being caused by a content filtering rule that we have enabled.  We have a content filter setup to scan the subject line of all messages that are internal, scanning to ensure that certain tags are used on all emails matched against a literal "Match List", if any message is found that does not contain something from the match list it is deleted, as set in the actions.  It looks like I need to replace this rule with a rule that perhaps has exclusions which would allow the Out Of Office messages to be deleted.  Does anyone have any idea how I could do this?  I'm guessing that I would have to use the regular expressions, but if I do this can I pass in Match Lists or variables such as %localtion%, %subject% or %sender%?