Print to File: why doesn't it work? (Acrobat Writer 8.1)

Hello,

I have a button, with which I want to print part of my PDF File to another PDF File.

I checked in the guide "Acrobat Javascript scripting reference". Unfortunately, the given code does not work.

var pp = this.getPrintParams();
pp.fileName = "/c/print/myDoc.prn";
this.print(pp);

It also does not work if I use"C:\temp\myPSDoc.prn". And not either if I replace "this.print" by simply "print".

Any good tip? Many thanks in advance for your help!

Cheers
Serge