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If you click on any of the IPs on the Bot Scout site, it's pretty clear that most attacks are being launched from PCs which have been infected with malware. One IP I looked at has over 20,000 matches!
If someone does build a Xoops module for Bot Scout, it would be good idea to inform banned visitors that they may have an infected PC, because I doubt that many victims will even know.
In their forum, this is the first thing they mention to people asking to be removed from the black list.
A thread is for life. Not just for Christmas.