>RBL support appeared in most other mailers *before* it was added to sendmail.

true.  rbl support wasn't part of sendmail's distribution until 8.9.0,
but there were easy to find and add rules that anyone could add long
before that.

>Sendmail is hardly the holy grail of mailer functionality.  In fact, it
>usually lags behind the times until its users scream loud enough for its
>maintainers to hear their pain.

what's it missing now that you still need?

-- 
|-----< "CODE WARRIOR" >-----|
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