Unfortunately this would not work if you add the RadCaptcha to the form for now. However thank you very much for showing us the need for such functionality. I have browsed our forums and it looks like the topic has been discussed several times, so we'll make sure to meet the customer demand by logging a task for the implementation of such a feature for the upcoming releases. Thanks a lot for the constructive feedback, and please stay in touch, we'll be happy to keep you updated on the task progress.
the Telerik team
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