 times, but never more often.
        </li>
      
</ul>
</div>
    
<a name="servlet-engine"></a>
<h2 class="underlined_10">Servlet Engines</h2>
<div class="section">
<p>
        When using a servlet engine, there are potential CLASSPATH issues, and potential conflicts 
        with existing XML/XSLT libraries. Servlet containers also often use their own classloaders 
        for loading webapps, which can cause bugs and security problems.
      </p>
<a name="tomcat"></a>
<h3 class="underlined_5">Tomcat</h