I would like to style a <ul> to display all items in a box with rounded corners (see below):

Is it possible to use CSS and only the <ul> (with no additional <div>s and tables), as I’m going to use it in a CMS system to style all <ul>s created by the user?
I was able to recreate your image using the following (X)HTML and CSS:
The end result looks like this:
screenshot http://img19.imageshack.us/img19/2194/screenshotdzn.png
But it only works in Firefox, Chrome, Safari and any browser supporting CSS3. That sadly excludes IE.