I set up a website that sends automatic html emails. The stock HTML templates included with the website are layed out using <div> tags and inline CSS code. <table> layouts are usually more appropriate for emails, however the <div> layout displays well in every email client I tested, except RoundCube. I haven't looked closely at the HTML output viewing RoundCube in my browser, but at first glance, I would guess that it has something to do with using CSS to position <div> tags in the layout of the RoundCube interface.
