title: What does "When <simpleContent> is used, the base type must be a complexType whose content type is simple..." even mean?
body: <p>Here's the whole error I keep getting from xerces.... </p>
  
  <pre>
  When &lt;simpleContent&gt; is used, the base type must be a complexType whose content type 
  is simple, or, only if restriction is specified, a complex type with mixed content
  and emptiable particle, or, only if extension is specified, a simple type.
  'string' satisfies none of these conditions.
  </pre>
  
  <p>I thought I understood this, but after getting it several times I must have lost it, anyone have a good "spin" on it</p>
  
  <p>I've narrowed it down to this element</p>
  
  <pre><code>&lt;xs:element name="Note"&gt;
    &lt;xs:complexType&gt;
      &lt;xs:simpleContent&gt;
        &lt;xs:restriction base="xs:string"&gt;
        &lt;/xs:restriction&gt;
      &lt;/xs:simpleContent&gt;
    &lt;/xs:complexType&gt;
  &lt;/xs:element&gt;
  </code></pre>
  
  <p>I think I've just been starring to long at the project...</p>