title: jQuery change document.location.href in input
body: <p>is it possible to use jQuery to do that:</p>
  
  <p>if the body has a <code>&lt;div id="wpadminbar"&gt;</code>
  then change the  document.location.href in this input from </p>
  
  <pre><code>&lt;input type="button" onclick="document.location.href='/wp-login.php?action=register';" value="Forum" id="forum"&gt;
  </code></pre>
  
  <p>to</p>
  
  <pre><code>&lt;input type="button" onclick="document.location.href='/forum';" value="Forum" id="forum"&gt;
  </code></pre>