a clarification for Ignore Spam Whitelist rule

[John Baker]

Hello

An organization who rents space from us over the summer had somebody 
unwittingly send out a mass mail with ,I'm told, some 1000 recipients 
under To: rather than Bcc: This got tagged by our mailscanner. I need to 
be sure that none of our own bulk mail out ever gets ignored by the 
whitelist.

I saw this in the log:

ignored whitelist, had 50 recipients (>20)

In my MailScanner.conf this is set to the default:

Ignore Spam Whitelist If Recipients Exceed = 20

So I'm looking for two points of clarification here if anyone can help.

1: Does this rule only trigger if the recipients are in the To: field 
and ignore recipients in the Ccc: or Bcc fields?

2: where does the 50 come from here? Is is just how many postfix or 
mailscanner would consider at a time?

Thanks
-- 
John Baker
Network Systems Administrator
Marlboro College
Phone: 451-7551 off campus; 551 on campus