I'm using SI CAPTCHA on a site where FORCE_SSL_ADMIN is set to "true" in wp-config.php. This means the register form is over SSL, too - but all the links for images and so on that SI CAPTCHA generates stay as HTTP. This means that if someone says "No" to "Display non-secure items?", the captcha is broken.
Is there anything I need to do to make SI CAPTCHA respect the FORCE_SSL_ADMIN setting? If it's currently not possible, I'm going to have to hack it - Mike, I'll send you the code for potential inclusion?