Where is cli.System.Object/IDisposable located?

Hello,

I would like to access an existing .net dll using java code, therefore
I used ikvmstub to generate the jar file containing the generated
interface file.
However, when I try to compile this code from NetBeans, it fails with:

> class file for cli.System.IDisposable not found
> class file for cli.System.Object not found

Indeed, the stub jar-file does not contain those classes.
Are they located in some support library?

Thank you in advance, Clemens

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