postfix and greylisting

[Dave]

Hello,
    I've set up greylisting with postgrey on postfix 2.3, on a 6.1 machine. 
All seems to be working well, except my bank can't get through, and i'm 
wondering how to let them through, what file to edit the user or the 
recipient file? Here's the output, confidential information x-d out.

Mar  5 11:56:18 zeus postgrey[630]: cleaning up old logs...
Mar  5 11:56:18 zeus postfix/smtpd[95256]: NOQUEUE: reject: RCPT from 
xxx[xx.xxx.xx.xxx]: 450 4.7.1 <xxx at example.com>: Recipient address rejected: 
Greylisted, from=<xxx at example.com> to=<xxx at example.com> proto=ESMTP 
helo=<xxx at example.com>
Mar  5 11:56:18 zeus postfix/smtpd[95256]: lost connection after DATA from 
xxx[xx.xxx.xx.xxx]
Mar  5 11:56:18 zeus postfix/smtpd[95256]: disconnect from 
xxx[xx.xxx.xx.xxx]
Mar  5 13:17:00 zeus postgrey[630]: cleaning up old logs...
Mar  5 13:17:00 zeus postgrey[630]: delayed 4842 seconds: client=xxx, 
from=xxx at example.com, to=xxx at example.com
Mar  5 13:17:00 zeus postfix/smtpd[95905]: C1A008: client=xxx[xx.xxx.xx.xxx]
Mar  5 13:17:00 zeus postfix/smtpd[95905]: lost connection after DATA from 
xxx[xx.xxx.xx.xxx]
Mar  5 13:17:00 zeus postfix/smtpd[95905]: disconnect from 
xxx[xx.xxx.xx.xxx]
Mar  5 13:20:21 zeus postfix/anvil[95907]: statistics: max connection rate 
1/60s for (smtp:xx.xxx.xx.xxx) at Mar  5 13:15:44
Mar  5 13:20:21 zeus postfix/anvil[95907]: statistics: max connection count 
1 for (smtp:xx.xxx.xx.xxx) at Mar  5 13:15:44
Mar  5 13:20:21 zeus postfix/anvil[95907]: statistics: max cache size 1 at 
Mar  5 13:15:44

My concern is the sending email server is going to time out this email, and 
it is rather important. I'd rather not turn off greylisting as i think it is 
useful and would rather like a solution. Googling has showed me how to 
configure greylisting, but not to add custom clients.
Any help appreciated.
Thanks.
Dave.