Empty pages after rendering images: org.apache.pdfbox.util.operator.pagedrawer.Invoke

Hello,
I'm printing file (test.pdf) which has on each page generated number with another font. I'm using PDDocument.loadNonSeq() to load data. In logs I can see
Feb 6, 2014 3:25:26 PM org.apache.pdfbox.util.operator.pagedrawer.Invoke process
WARNING: Can't find the XObject for 'Xf1'
and no data except that generated numbers are printed.

I've seen in some old bug that imageIo library was needed, but now in dependencies I don't see it (http://pdfbox.apache.org/dependencies.html)

Please can you fix this?

Thanks