[xwiki-users] Captcha for comments

Hi guys, I've upgraded to XWiki 2.3. In the docs, it says: "To turn on comment captcha requirement, go to wiki or space administration, click on the "Rights" section and notice the checkbox toward the bottom labeled "Require unregistered users to solve a captcha when posting a comment on a page". Check that box and guests will be required to solve a captcha to comment." However, when I go to the "Rights" section, I do not see any checkbox saying "Require unregistered users to solve a captcha when posting a comment on a page". I've already imported the latest xar-archive. Could anyone shed some light how to get this new feature working? TIA Gregor -- just because you're paranoid, don't mean they're not after you... gpgp-fp: 79A84FA526807026795E4209D3B3FE028B3170B2 gpgp-key available @ http://pgpkeys.pca.dfn.de:11371 @ http://pgp.mit.edu:11371/ skype:rc46fi