I am the Exchange Administrator - and would fully cooperate with myself if I
knew how to do what you propose ... why did they make it so hard to do ?
UNIX is just a simple variable change in a .vacation file.

Paul

It is complicated -- http://msdn.microsoft.com/exchange/ -- and unless you
have the cooperation of the Exchange administrator, you won't get very far.

The client-side alternative is to leave Outlook running 24/7 with a Rules
Wizard "run a script" rule for each DL. A "run a script" rule action
actually uses not an external script but a VBA procedure with a MailItem or
MeetingItem as its parameter. That item is processed by the code:

Sub RunAScriptRuleRoutine(MyMail As MailItem)
   Dim strID As String
   Dim olNS As Outlook.NameSpace
   Dim oMail As Outlook.MailItem
   Dim myReply as Outlook.MailItem

   strID = MyMail.EntryID
   Set olNS = Application.GetNamespace("MAPI")
   Set olMail = olNS.GetItemFromID(strID)
   ' do stuff with oMail, e.g.
   Set myReply = oMail.Reply
   myReply.Subject = "Thank you for your email regarding " & oMail.Subject
   myReply.Send

   Set olMail = Nothing
   Set olNS = Nothing
End Sub

That won't work, though, unless you have Outlook 2003, because of the Send
method security prompts.