HttpServletRequest not found from within library

[Christian Hauser <c....@active.ch>]

Hello all

I'm using Tomcat 4.1.24 and have the following problem.

In a JSP file I have a bean called nav pointing to a class 
some.package.Navigation. This class is located at a JAR file in the lib 
directory of the web application.

...
<jsp:useBean id="nav" class="some.package.Navigation" 
scope="session"></jsp:useBean>
<%
nav.handleRequest(request, ...);
...

In the Navigation class I get a
java.lang.NoClassDefFoundError: javax/servlet/http/HttpServletRequest

But the HttpServletRequest Interface is imported:
import javax.servlet.http.*;

Furthermore the CLASSPATH contains the path to servlet.jar, which also 
is located in <CATALINA_HOME>/common/lib.

I can't figure out why I get this error and how to make it find the 
servlet.jar.

Thank you in advance for every hint.

   Christian