I have just converted the Pivot http:BL snippet to a PivotX extension. The http:BL extension can protect your PivotX site from search engines, suspicious (IPs), harvesters, comment spammers, or a combination thereof using the http:BL service from the Honeypot project - see http://www.projecthoneypot.org/httpbl_api.php All blocked domains (IPs) are added to the spam log.
Download location: http://extensions.pivotx.net/entry/19/httpbl
Instructions: Download the zip file, unzip it and upload the folder "httpBL" to your extensions folder on your server. Then enable and configure the extension in the PicotX administration. Check your spam log, example.org/pivotx/index.php?page=spamlog, from time to time to see that it works.