title: How to use custom 404 page on not found controller/action
body: <p>I have wrote a custom <code>404 Page Not Found</code> page. 
  But where I have to put it in my Zend Application structure and how to show it? </p>
  
  <p>When a controller couldn't be found I receive an <code>Invalid controller specified (dsa)</code> error. 
  And when an action couldn't be found I receive an <code>Action "wqe" does not exist and was not trapped in __call()</code> error. </p>
  
  <p>Shortly, I don't want these errors.</p>
  
  <p>How can I detect if the page is not found before rendering? And when I detect it, how can I show my custom error page. At the moment I receive the errors from above but the layout is still displayed. </p>
  
  <p>Do I need some <code>.htaccess</code> rules? Or it can be done with some Zend stuff.</p>