In the bidi.css file, the rule for the Captcha doesn't have .rtl in front of it like the rest of the rules in the bidi file.

File:

bidi.css

Find:

    .captcha-panel dd.captcha {

        margin-right: 0;

    }

Change To:

    .rtl .captcha-panel dd.captcha {

        margin-right: 0;

    }