Milter-greylist

At the moment the DNSRBL syntax is something like:

   dnsrbl "BLAH" dnsbl.blah.blah 127.0.0.2

It would be useful to extend the syntax to allow zero or more dotted 
quad addresses.

e.g. To greylist any IP address which has a corresponding "A" record in 
an RBL:

   dnsrbl "ALL BLAH" combined.blah.blah

Also useful would be repeating dotted quad addresses to match (implicit 
"or"):

   dnsrbl "SOME BLAH" combined.blah.blah 127.0.0.2 127.0.0.5 127.0.0.10

This would come in useful for greylisting countries by (for example) 
querying zz.countries.nerd.dk and listing the returned addresses you 
wish to match.

Cheers,

Phil