title: XSD validates wrong format of xs:date and xs:dateTime
body: <p>When I set the <strong>year</strong> section like below (20512 or anything like this), XSD still validates XML.</p>
  
  <p>Any idea.</p>
  
  <p>Is this a flaw or do I have to use <strong>simpleType</strong> with given pattern?</p>
  
  <p>Thanks</p>
  
  <p><strong>XSD</strong></p>
  
  <pre><code>&lt;xs:attribute name="date" type="xs:date" /&gt;
  
  &lt;xs:attribute name="timestamp" type="xs:dateTime" /&gt;
  </code></pre>
  
  <p><strong>XML</strong></p>
  
  <pre><code>&lt;store date="20512-07-11" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="items.xsd"&gt;
  
  &lt;store timestamp="20512-07-11T21:50:16" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="items.xsd"&gt;
  </code></pre>