Indeed when setting a tooltip to the node and there is an ImageUrl
property set, the tooltip is set as an alt
property of the rendered image on the page (thus, displaying the tooltip only when the image is not present). I will forward your request to our development team so they can review this scenario and possibly include it as a future improvement of the control. Meanwhile I can suggest that you use template where you can place any control and set its tooltip as desired.
If you want to get updates on new releases, tips and tricks and sneak peeks at our product labs directly from the developers working on the RadControls for ASP.NET AJAX, subscribe to the blog feed