trying to solve an itext java error running a RPG ILE application

Hi all
I'm trying to use itext java library to create pdf files. A basic part of
work is done, but testing a simple case fails when closing pdf document.
Probably the close method really fails due to previous errors, and I'm
trying to found them. I have created a trace file, and have got this output:

Exception in thread "main"# START
NON-TRANSLATABLEjava.lang.NullPointerException
at java.lang.String.compareToIgnoreCase(String.java:603)

at java.io.BufferedOutputStream.flushBuffer(BufferedOutputStream.java:94)

at java.io.BufferedOutputStream.flush(BufferedOutputStream.java:152)

at
com.itextpdf.text.pdf.OutputStreamCounter.flush(OutputStreamCounter.java:89)

at com.itextpdf.text.DocWriter.close(DocWriter.java:233)

at com.itextpdf.text.pdf.PdfWriter.close(PdfWriter.java:1341)

at com.itextpdf.text.pdf.PdfDocument.close(PdfDocument.java:901)

at com.itextpdf.text.Document.close(Document.java:415)

It is the first time I see # START NON-TRANSLATABLE statement, and haven't
located it in IBM documentation. Only a reference in Eclipse, which I don't
use here.
It is probably an issue related to CCSID and it is my first area of
revision now. Probably there is a conflict between text (a simple Hello
world) and properties or job definitions.
But if any of yours have dealt with such statement, it would help me to get
context on it.
Kind regards
Jorge Ubeda