title: "This element is not expected" while using 'any' with xhtml namespace
body: <p>I have some issues with XML Schema. I need to put some HTML code in my XML file and I found that xs:any would help. But xmllint return me errors like this:</p>
  
  <pre><code>example.xml:4: element h1: Schemas validity error : Element 'h1': This element is not expected. Expected is ( {http://www.w3.org/1999/xhtml}* ).
  </code></pre>
  
  <p>XML:</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="UTF-8"?&gt;
  &lt;foo&gt;
  &lt;bar&gt;
      &lt;h1&gt;Lorem ipsum&lt;/h1&gt;
  &lt;/bar&gt;
  &lt;/foo&gt;
  </code></pre>
  
  <p>Schema:</p>
  
  <pre><code>&lt;?xml version="1.0"?&gt;
  &lt;xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"&gt;
  &lt;xs:element name="foo"&gt;
      &lt;xs:complexType&gt;
          &lt;xs:sequence&gt;
              &lt;xs:element name="bar" minOccurs="1" maxOccurs="unbounded"&gt;
                  &lt;xs:complexType&gt;
                      &lt;xs:sequence&gt;
                          &lt;xs:any namespace="http://www.w3.org/1999/xhtml" /&gt;
                      &lt;/xs:sequence&gt;
                  &lt;/xs:complexType&gt;
              &lt;/xs:element&gt;
          &lt;/xs:sequence&gt;
      &lt;/xs:complexType&gt;
  &lt;/xs:element&gt;
  &lt;/xs:schema&gt;
  </code></pre>
  
  <p>What I do wrong?</p>