If you set your GreyListing to only delay for 1 minute, see the settings in my antispam documet, see:
https://portal.chicagonettech.com/kb/a171/smartermail-antispam-settings-document.aspx,
You'll still take advantage of the very powerful tool that GreyListing provides, and minimize the delay in receiving from "unknown" recipients.
A new version will be pushed out in a couple of weeks, so check back often.
Bruce Barnes
ChicagoNetTech Inc
brucecnt@comcast.net
Phonr: (773) 491-9019
Phone: (224) 444-0169
E-Mail and DNS Security Specialist
Network Security Specialist
Customer Service Portal: https://portal.chicagonettech.com
Website: https://www.ChicagoNetTech.com
Security Blog: http://networkbastion.blogspot.com/
Web and E-Mail Hosting, E-Mail Security and Consulting