I know it's not the exact answer you were looking for, but your typical sendmail logfile contains all the info you're asking for, without tweaking. It would be much easier to write a quick script to parse the logfile instead of writing a server. I've seen a few scripts floating around, a few of them are registered on perl.com

In reply to Re: SMTP logging server by elwarren
in thread SMTP logging server by Anonymous Monk

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