"Bad Behavior" behaves badly, again

Several of the sites I run all started reporting the same error suddenly:

We’re sorry, but we could not fulfill your request for /forum/newreply/8973/ on this server. Your Internet Protocol address is listed on a blacklist of addresses involved in malicious or illegal activity. See the listing below for more details on specific blacklists and removal procedures. Your technical support key is: 80df-d021-1366-73cd You can use this key to fix this problem yourself. If you are unable to fix the problem yourself, please contact webmaster at samharris.org and be sure to provide the technical support key shown above.

I couldn’t fix it, and so I’ve disabled Bad Behavior all my sites. Anyone else have details on what might be causing this?

(The “behaving badly again” stems from an issue last month where bad behavior appeared to be blocking GoogleBot from visiting one of my sites http://ellislab.com/forums/viewthread/63850/)

TTFN Travis