I'm using Kareha.
I want to reload captcha image on click. My idea is to delete the captchakey cookie and to rerequest captcha.pl. So, I can delete to cookie using javascript
var cookie_date = new Date ( ); // current date & time
cookie_date.setTime ( cookie_date.getTime() - 1 );
document.cookie = "captchakey=; expires=" + cookie_date.toGMTString();
Now, given, that kareha captchakey generation mechanism is based on the REMOTE_ADDR and time() in minutes (string 61 in captcha.pl), if I rerequest the captcha within one minute, I'll get the same image.
However, when a user successfully post a message, the captcha is generated randomly (string 430 in kareha.pl).
So, I could follow this way, but before doing this I want to understand, what was your reasons for such design?