When adding custom dialogs (as explained at http://docs.telerik.com/devtools/aspnet-ajax/controls/editor/functionality/dialogs/custom-dialogs) we provide a toolbar icon for each dialog.
Those custom icons are used in the default 'classic' rendering mode of the editor.
But... when using RenderMode=auto, those icon-images are replaced with gear wheels.
How can we provide our own icons for other rendering modes than the 'classic' mode?