Yes this would be very possible.
A number of ways to do this would be:
1) create a VSTO (Visual Studio Tools for Office) addin for outlook. You can listen for events which occur on the inbox which means you can act on an event when a email arrives in the inbox. You can then parse the mail item from the outlook explorer / instance object and check for say the wording in the subject or body. If this is detected you can easily send a response automatically.
The downside here is that a user would have to be in outlook for this to be working.
http://msdn.microsoft.com/en-US/office/hh128768[
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2) Create an application or service that polls a mail box or public folder in exchange. It could then read emails from within the the mailbox and respond accordingly.
http://msdn.microsoft.com/en-us/library/dd877045(v=exchg.140).aspx
http://www.dimastr.com/redemption/home.htm
http://www.emailarchitect.net/eagetmail/kb/csharp.aspx?cat=2
If you can use EWS and not mappi although both work well.
3) Have your butler do it.
Kind regards