Print function doesn't work, missing in some node

i use this print modules to a pdf files from a node
almost in all node the print modules work very good
but i got a node where this print modules not working at all
for example :
i use

				print print_pdf_insert_link();

to generate the link to create a pdf files, in every node the link is shown up, but in this node this link not appear at all
and when i use manually cal the URL to print the pdf, fromthat node it is running, but when i open the file it is empty

i think this a bug