[Exim] Help please..

I have a friends server that is running exim, and they lost about 1/4 of
the /etc/passwd
unitll I can write a script to recreate this, how can I make exim write
to the /var/mail/$UID

if the account does not exist, yet the mail box does? At least so it
will quite bouncing mail for a couple hours...

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Derrick MacPherson
Mercury Filmworks