RE: declaring an element having subelements and restricted child-text-node value

> How can I declare an element that satisfies the following:
> 1) it has subelements and
> 2) the value of its child-text node is restricted (to belong 
> to a set of values), just as in the example above?

You can't. With mixed content, (that is, text nodes and element nodes as
siblings of each other) you can't restrict the content (or position) of the
text nodes.

It's best to avoid using mixed content this way - mixed content is designed
for marking up continuous text.

Michael Kay
http://www.saxonica.com/