Problem with addAltChunk/convertAltChunk

[bs_dellacqua]

I'm using docx4j v8.3.0 and I'm trying to use addAltChunk/convertAltChunk to create a docx file inserting an xhtml, and then convert the docx in PDF, but it seems that the conversion doesn't work, in the pdf file I've the message "NOT IMPLEMENTED: support for w:altChunk".
I attach the Java source file, the used pom, the created docx file, the final pdf file.
Before v8.3.0 I executed successfully
wordMLPackage.getMainDocumentPart().getContent().addAll(indexOfParentText, XHTMLImporter.convert(xhtml, null));
but now the generates an exception that I've reported in another issue.