Milter-greylist

Hi,

I'd like "reduce" milter-greylist to one function: do URL lookups
(checking the recipient through a webservice) 
and reject (not greylist) emails with a "554 5.7.1" code if the answer of
the lookup is not "milterGreylistStatus: Ok". It's a kind of call
forward/ahead against an internel webbased service and not against a smtp
server like "md_check_against_smtp_server" function in mimedefang.

Thanks
Marcus