Keeping several spamds in sync

Starting with OpenBSD 4.1, you can sync greylists

spamd command line flags:

-Y sync target

-y sync listener

on mainoffice-gw.example.com

-Y minorbranch-gw.example.com -y re0

on minorbranch-gw.example.com

-Y mainoffice-gw.example.com -y re0