If the RECAPTCHA_VERIFY_SERVER (google.com) is down, recaptchalib will die() when it tries to contact the server. It would be better for it to fail gracefully.
This issue in the recaptchalib.php queue.
reCAPTCHA will now test that the server is up before asking recaptchalib to verify the user's input. Fixed in 24f9d99.
Issue #1734956: Test that the reCAPTCHA server is up before asking...
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