When I specify the value of EditorWysiwygModeCss in the Server Tag 
        <CE:Editor ... EditorWysiwygModeCss="client.css" .../>
Everything works as expected.  The classes are listed in the drop-down menu of classes and the text renders correctly in Normal view.

But when I use server-side code instead (in the Page_Load subroutine), 
        Editor1.EditorWysiwygModeCss = getSiteCss()
the page renders correctly in the editor, but the classes are not listed in the drop-down menu.  The menu is empty.

I want to control the classes in the dropdown under software control, so I need to use the second form.  I would rather not write additional code to build up the drop-down menu under program control.

Is the difference in behavior depending on the context of the css specification a bug you will fix soon?  Do you have another suggestion?

 

Thanks