A tinymce editor doesn't work if you put it into a jQuery dialog, it loads but you can't edit the text inside. It's also impossible to set or get the html out of the editor through:

tinyMCE.execInstanceCommand("editor2", "mceSetContent", false, "mycontent", true);

It seems to be a problem with the dynamic addition of the dialog wrapper tags, if you add the dialog html in a static way the editor works just fine.