Ant, jar files and names libraries

Hi,

I want to accomplish the following...

I want a jar file that I can double-click in windows so it will run on its
own.
I am using the Xerces and Xalan library in my project.

So far I can compile the project in idea and compile and create a jar file
with ant in idea.
If I copy the classes in the xalan and xerces library jar files (manually)
to my project jar file and set the jar
file association in windows then I have what I want. But of course I would
like to do this automatically somehow
in idea with ant.

The first question I have is how I reference my idea named libraries in the
ant script and copy classes from it?

Is there some other way to create the jar file without copying the classes?
Can I copy jar files in jar files and
get the same result somehow?

And finally... is there some way that only the imported/needed classes are
copied automatically?

Thanks for any help.

Robert.