Error 500: Internal servlet error

[white_power <wh...@freemail.hu>]

Hello everybody !

I'm an absolute beginner in using tomcat, and I have a little (?) problem. 
The situation is:

I'm using RedHat linux + jdk1.3 + tomcat3.2.1. I compiled a
simple servlet to the TOMCAT_HOME/classes/session/WEB-INF/classes
directory, named ServletSession.class. The web.xml is the following:


...
<web-app>
	<servlet>
	<servlet-name>ServletSession</servlet-name>
	<servlet-class>ServletSession</servlet-class>
	</servlet>
	<session-config>
	<session-timeout>
		5
	</session-timeout>
	</session-config>
<web-app>

In the server.xml there is a <context> entry:

...
<Context path="/session" docBase="classes/session">
</Context>
...

When I type the http://localhost:8080/session/servlet/ServletSession URL I
always get this error:

Error: 500

Location: /session/servlet/ServletSession
Internal Servlet Error:
java.lang.NullPointerException 
	at java.lang.ClassLoader.resolveClass0(Native Method)
        at java.lang.ClassLoader.resolveClass(ClassLoader.java:588)
        at
org.apache.tomcat.loader.AdaptiveClassLoader.loadClass(AdaptiveClassLoader.java:430)
        at
org.apache.tomcat.loader.AdaptiveServletLoader.loadClass(AdaptiveServletLoader.java:174)
        at
org.apache.tomcat.core.ServletWrapper.loadServlet(ServletWrapper.java:265)
        at
org.apache.tomcat.core.ServletWrapper.init(ServletWrapper.java:289)
        at org.apache.tomcat.core.Handler.service(Handler.java:254)
        at
org.apache.tomcat.core.ServletWrapper.service(ServletWrapper.java:372)
        at
org.apache.tomcat.core.ContextManager.internalService(ContextManager.java:797)
        at
org.apache.tomcat.core.ContextManager.service(ContextManager.java:743)
        at
org.apache.tomcat.service.http.HttpConnectionHandler.processConnection(HttpConnectionHandler.java:210)
        at
org.apache.tomcat.service.TcpWorkerThread.runIt(PoolTcpEndpoint.java:416)
        at
org.apache.tomcat.util.ThreadPool$ControlRunnable.run(ThreadPool.java:498)
        at java.lang.Thread.run(Thread.java:484)

I tried to solve this problem, but now I haven't any idea. 

Please help me, if you can.

thanx: Hajdu Erno.