Use the mail-sorting contrib from dungog.
http://www.dungog.net/wiki/Smeserver-mailsorting
Should see you right. Might mean you have to create a lot or rules, but it works a treat.
Thanks,
I'm very late in checking this response
I was sort of hopeing for something simple that would just allow me to only accept email from those on my address book.
Most clients and even many webmail offer this already.
That way I could potentially get emails only from those that I made personal contact with or talked to on the phone and physically entered their mail into the address book.
Perhaps I can create a subject filter so that only mail with that keyword in the subject line will go through that way I know only those people that I talked to or contacted will only be able to send me mail on that account.
I'll check out the filter rules and thanks for the response.