title: <a4j:commandButton> doesn't work on second click
body: <p>I am having a <code>rich:popupPanel</code> on page which takes some text as input and I have put validation on that input text field. Now if we press <code>&lt;a4j:commandButton&gt;</code> first time it will execute everything properly, but second time won't work.</p>
  
  <pre><code>&lt;a4j:commandButton styleClass="button" id="addFieldBtn" value="#{msg.Add}"
     oncomplete="if(#{messageDataBean.isSuccess}) {#{rich:component('fieldPopUp')}.hide();}"
     action="#{categoryServiceBean.addAddtionalFields}" render="fieldList"/&gt;
  </code></pre>
  
  <p>My <code>messageDataBean</code> and <code>categoryServiceBean</code> are request scoped.</p>