5/28    My .spamassassin directory takes up about 1/3 of my quota.
        Roughly half of this directory is my bayes_toks file.  The
        other half is nearly entirely filled up by a whitelist-db
        file that hasn't been modified in over a month.  It's over
        4Megs and seems to contain a bunch of stuff I don't even
        recognize.  There is also another whitelist file that is
        much much smaller.  What is the meaning of these files?  Do
        I need them?