GFI MailEssential Exchange 怎么不起作用？？

antsly

前段时间因为垃圾邮件的问题俺装了一个GFI MailEssential for Exchange，经过俺一翻设置，别说还真管用垃圾邮件好像一夜之间全部蒸发啦！
可从12/23号到今天，好像它丢去了以前的作用，几乎每天都可以收到一、两封垃圾邮件，而且我看了一下，和以前被过滤掉的属一类垃圾。
我看了一下日志记录，发现sender policy framework还是启作到的。这是昨天刚过滤掉的日志：""12/27/07 21:35:42","SPF","gordon_givens@shaw.ca","****@*****","RE: December 72% OFF","Deleted","Sender is probably forged (SPF Softfail)"
但dns blacklists和bayesian analysis好像不启作用啦！日志停到了12/23日那里就再也没有记录过。"12/23/07 18:03:59","DNS Blacklist","epoMaster@asus.com.tw","***@*******","Please confirm new/changed order in Asus EPO system","Deleted","Sending mail server found on xbl.spamhaus.org"

我用的是破解版的GFI MailEssential for Exchange，请高手们指点一上，这是为什么？？？