installing VisAD using visad.jar

xu@xxxxxxxxxxx

I try to install VisAD (using visad.jar) in the following way (as shown
in FAQ).

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        1.Install JDK 1.2 or JDK 1.3 from Sun's web site.
         2.Optionally, install Java3D 1.1.3 from Sun's Java3D
         3.Download the visad.jar file from the VisAD web site.
         4.Set your CLASSPATH environment variable to point
           to the location of the visad.jar file that you just
downloaded.
         5.Try running the VisAD SpreadSheet to verify your
           installation:
                 java visad.ss.SpreadSheet

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But when I run  java visad.ss.SpreadSheet, I got the following error
message.

Exception in thread "main" java.lang.NoClassDefFoundError:
visad/ss/SpeadSheet

I have no ideas. I hope to get some help.

Thanks