[exim] Sorting and sending multiple copies of a mail

Hi all,
I tried to find out something in the archives that could help me
resolving my little problem but I wasn't able to find anything.
Sorry if I'm too Exim-stupid to resolve it by myself.
Anyhow, this is my trouble:
I'm using Exim4 on a little mail server based on debian sarge.
Now, I need to redirect mails sent to a specific email account to
different accounts on the box, possibly sorting them if they contain
some keywords in the subject or in the message body (such as the name
of the person the mail is intended to arrive to). In the eventuality
there are no corrispondences with the keywords, the mail got to be
sent to the entire group of accounts.
Is it difficult to realize? I'm not expert at all with Exim, so let me
know anything I should do to achieve the result.
Thanks a lot in advance.

Matteo


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