Milter-greylist

> 
> As far as I saw, the only place to require a string form of an IP
> address is the dumping, except error message outputs.
> 

And there is a place in MX sync.
More precisely it is used in pending_del() for address comparison.
Of course, it may be replaced via comparing the content of the sockaddr structs.

Bests,
Attila