With this option enabled, SpamSieve will never predict a message to be spam if its sender’s e-mail address is in the system address book.
You can add addresses to the system address book using the Address Book application (located in the /Applications folder), or directly from an e-mail program that supports the system address book.
PowerMail users should be sure to enable the option to use Apple’s Address Book. Entourage users may prefer to use their address book as a whitelist instead of Apple’s. This is described in the Setting Up Entourage section.
If spam messages get through to your inbox because they are sent from addresses in your address book, you can either uncheck Use Mac OS X Address Book or see the Exclude my addresses section. For more information, please see the How do I make SpamSieve catch spams sent from my own address? section.