I'm not sure exactly what you're asking here, so please forgive me if I answer the wrong question.
You can put packages and JARs in the directory C:\jk1.3\jre\lib\ext, and you will not need to explicitly set the classpath to find these. This is intended for JAR files that you might use frequently (ext = extensions), such as crypto classes.
Note that a common gotcha here is to be sure that if you have put the classes in C:\jk1.3\jre\lib\ext, that you are actually using c:\jdk1.3\bin\java, and not some other jvm.
I haven't heard of there being a feature that you describe (eg. putting classes in jdk1.3\jre\classes), although I suppose it is possible there is - I don't have jdk1.3 on this machine to
test that theory. If the feature does indeed exist it doesn't sound like something I'd advise anyone use though. You're much better off setting the classpath explicitly (in your environment or via the -classpath flag) so that always you know exactly what classes are in your classpath. Inadvertently leaving old classes in your classpath can lead to a lot of confusion!
Rob
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Rob Ward
rob.w@mail.com "Maths and alcohol do not mix. Remember, don't drink and derive"