For the time being you can use the following JavaScript workaround: <html xmlns="http://www.w3.org/1999/xhtml"> <head id="Head1" runat="server"> <title></title> <script src="//ajax.googleapis.com/ajax/libs/jquery/1.8.3/jquery.min.js"></script> <script src="//ajax.googleapis.com/ajax/libs/jqueryui/1.10.4/jquery-ui.min.js"></script> </head> <body> <form id="form1" runat="server"> <telerik:RadScriptManager ID="RadScriptManager1" runat="server"> </telerik:RadScriptManager> <telerik:RadFormDecorator ID="RadFormDecorator1" runat="server" /> <script> //Workaround: var removeCssClass = Sys.UI.DomElement.removeCssClass; Telerik.Web.UI.RadFormDecorator.prototype.set_elementDisabled = function (element, val) { var actor = element; var nextSibling = element.nextSibling; var type = element.type; if ((type == "checkbox" || type == "radio") && nextSibling && nextSibling.tagName == "LABEL") { actor = nextSibling; } else if (type == "button" || type == "reset" || type == "submit" || element.tagName == "BUTTON") { var parent = element.parentNode; if (parent && parent.tagName == "A") { actor = parent; parent.disabled = val; } } if (val) addCssClass(actor, "rfdInputDisabled"); else removeCssClass(actor, "rfdInputDisabled"); try { if (!val && $telerik.isIE && actor.parentNode.disabled) { actor.parentNode.disabled = val; } } catch (e) { } } </script> <input type="button" value="Test" onclick="Run(); return false;" /> <div id="TestDiv" style="display: none"></div> <script type="text/javascript"> function Run() { $('#TestDiv').dialog({ modal: true, buttons: { "OK": function () { alert('bye'); } } }); } </script> </form> </body> </html>