[exim] Exim before-queue filtering?

With Postfix, it is possible to do "before-queue filtering"[1] (where
mail is accepted only when filtering says it's OK).

Can I make a similar setup with Exim? If yes, could you point me to Exim
documentation describing such setup?


[1] http://www.postfix.org/SMTPD_PROXY_README.html


--
Tomasz Chmielewski
http://wpkg.org