Can't deploy a servlet using the deploytool

[ming zhu]

Have spent lots of time, but still can not figure this out.
I downloaded J2EE 1.4.2 with sunwappserver.
When I tried to create a WAR file with servlet, an error message box showed up indicating the servlet class has not been added. I knew I did since the class file has been added to the Content under WEB-INF/Classes...
When I tried to create a WAR file with JSP, it worked.
What did I miss here?
Please help.