recaptchalib calls die() in various conditions. It would be much better to detect these conditions before they happen and handle them gracefully.
Mostly fixed in b03a8d9; patch attached. There is one condition under which die() will be called that it not fixed here. New issue for that: #1734956: Fail gracefully instead of calling die() if reCAPTCHA server is down.
This is an expansion of the work in #1681746: Page is blank when reCAPTCHA not configured.
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