NoClassDefFound error in Signed Applet

[Phua Kia Ming]

Subject: NoClassDefFound error in Signed Applet

Hi,

I've been trying to run a signed applet under Netscape
Communicator 4.7, but I keep getting a NoClassDefFound
error on the Netscape's JVM. I've packaged and signed the
applet into a JAR file will all the required components
(Swing classes, Netscape classes, etc), all with the
correct path names. But I still keep getting the same
error! The applet was written, compiled and packaged
using JBuilder 3 (JDK 1.2).

This has been bugging me for more than a month now and
I need to solve this for a project presentation.
Could anyone please help? Thanks a lot!

Regards,
Kevin Phua
NTU, Singapore.

Here's the error message from Netscape's Java Console:
------------------------------------------------------

Netscape Communications Corporation -- Java 1.1.5
Type '?' for options.
Symantec Java! ByteCode Compiler Version 210.065
Copyright (C) 1996-97 Symantec Corporation
Local address = 155.69.144.218

# Applet exception: error: java.lang.NoClassDefFoundError:
javax/swing/JFrame

java.lang.NoClassDefFoundError: javax/swing/JFrame
at Jiphone.<init>(Compiled Code)
at netscape.applet.DerivedAppletFrame$LoadAppletEvent.dispatch(Compiled
Code)
at java.awt.EventDispatchThread$EventPump.dispatchEvents(Compiled Code)
at java.awt.EventDispatchThread.run(Compiled Code)
at
netscape.applet.DerivedAppletFrame$AppletEventDispatchThread.run(Compiled
Code)

-------------------------------------------------------------

[Solo Technologies Limited]

I am getting the same error even without packaging it in a JAR file. It
doesn't seem to find
javax.swing package

I've checked my Java VM plug in for NN - through HELP::About Plug-ins menu
option from the NN. It says that I have Java 1.2.2 installed:

---------
Java Plug-in 1.2.2 for Netscape Navigator

File name: C:\PROGRAM
FILES\NETSCAPE\COMMUNICATOR\PROGRAM\plugins\npjava32.dll

Java Plug-in 1.2.2 for Netscape Navigator with JDK/JRE 1.2.2
---------

This is bugging me too. None of the applets using Swing are working. The old
traditional AWT applets work with no problems. Anyone knows the solution?

Regards,
Greg