create jar file with external jar library

Hi,
in my application there are several import from an external library, in
Eclipse i've added this library in Project -> Properties -> Java Build
Path -> Add External JARs.

Well, when i export as a Jar file this "jade.jar" library is not in my jar
file and the application cannot run.

I've tried even to manually modify the manifest.mf file adding the row:
Class-Path: jade.jar (adding even the file in the jar)... but this is not a
solution

Is there a solution?


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