How to use the X-Loop field when resending mail

Hello,

I do have the following problem:
I want to send an customized e-mail with procmail. So I added the sender
address to the X-Loop: field to prevent mail-loops as stated in procmailex.

However the circumstances are as following:

user: 'robot'
e-mail address for automated replies: 'service' which is actually an alias, to 'robot'

Mails to the 'service' address have to have a certain subject to be parsed correctly.
Any other messages are discarded and an informational message is returned.
On the other hand I want the user to be able to reply to an different address 'service-admin' (which also is an alias for 'robot') if they encounter any problems with
the automatic replied mail.

So which e-mail addresses do I have to include in the X-Loop: field, and in which form?
Notice that our mailer also rewrites the sender address, so service(_at_)my(_dot_)org will result
to service(_at_)some(_dot_)org (which is correct).

I guess I have to write:
X-Loop: service(_at_)some(_dot_)org, service(_at_)my(_dot_)org

On the other hand I guess I don't understand the deeper purpose of the X-Loop: field at all ...
Many thanks in advance,

  Bernhard.
  

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 Bernhard Scholz			 http://www.leo.org/~scholz/
Peanuts FTP Admin 			http://peanuts.leo.org/
scholz(_at_)leo(_dot_)org (StuSta ONLY: boerny(_at_)xenia(_dot_)hsh(_dot_)stusta(_dot_)mhn(_dot_)de)