It is not currently possible to enable a captcha on the login page, and to be honest that sounds like a bad idea to me. No sites I use require a captcha to login. That would be quite a nuisance and discourage use of your site.

I can see where you might like to have a captcha on the registration page and I have a to do list item to make that possible, but currently it is not possible. What we have now is a setting in site settings where you can require that the email address used for registration must be validated before the user can login. When this is enabled, when a user registers it sends them an email with a link they must click to activate the account. Only then can the user login.

Hope it helps,

Joe

I will add a wish list item in my project tracker for this, maybe I will implement it at the same time when I do it for the registration page.

Note that there are settings in Site Settings to control how many failed login attempts before an account is locked temporarily. So if you define that as say 5 attempts in a 5 minutes then what happens if there are 5 failed attempts within a 5 minute period then the account will be locked for 5 minutes.

Best,

Joe