The specified pieces of code, displayed in your post, do not appear to be part of the current version of the RadControls for ASP.NET AJAX. I have attached the SpellCheckService.js for reference. Could you, please, specify the version of the controls that you are using in your application? Furthermore we will need more information from the security check so that we can review if that is indeed a real issue or a false alert, like scenario of usage, controls that are causing the security warning, etc.
the Telerik team
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