Merging PDFs created using "Nuance PDF Create" not possible

Merging PDFs created using "Nuance PDF Create 8" is not possible:

• Merging two PDFs created using "Nuance PDF Create 8" results in a corrupted PDF.
• Merging one PDF created using "Nuance PDF Create 8" with another PDF ignores the PDF from Nuance.

Command lines to reproduce the problem:
java -jar pdfbox-app-1.8.8.jar PDFMerger nuance-pdf-test.pdf nuance-pdf-test.pdf result.pdf
java -jar pdfbox-app-1.8.8.jar PDFMerger otherpdf.pdf nuance-pdf-test.pdf result.pdf