IIRC, they're working on that; check the Greylist ML archives (at http://lists.puremagic.com/pipermail/greylist-users/2004-March/thread .html) for the thread "Bagley: version 0.01 available"; you should find a link to
http://workingcomputers.eris17.co.uk/bagley/bagley-0.01.tar.gz
which apparently works with Exim 4 using either an ACL hook or local_scan. I know zero about Exim but apparently calling it from an ACL hook allows RCPT-time rejection.
Thanks - something to play with this weekend :) I see the original author of the Exim greylisting code is implementing it as an ACL, too.
Mike.
