[Exim] collecting outgoing mail

Hi!

I would like to collect all outgoing mail from our server to a local
mailbox. I tried to add a Bcc: header and tried to write out with the
appendfile driver but I failed on user access rights. Maybe there is a
simpler way... (?)

If anybody had a similar problem or has an idea, please reply me in
private (I'm not a member of this list)!

Thanks in advice,
    Bence Sztanyik

PS: exim rules, anyway! :)