title: f:validateRegex doesn't show any message after typing invalid character
body: <p>I'm using JSF. With code for validating:</p>
  
  <pre><code>&lt;h:inputText id="sender" value="#{contactForm.sender}"&gt;
        &lt;f:validateRegex pattern="([a-zA-Z_0-9]).{4,32}" /&gt;
  &lt;/h:inputText&gt;
  </code></pre>
  
  <p>When i type a string: abc. The result is invalid. Good.
  Then i type: abcd@ . I thought, that string is invalid because that string contains @ letter. But i don't recieve any messages. That means that string is valid. I don't understand about regex clearly. Can you help?</p>