problem moving to nginx

Hi all , just getting my head around Nginx

i have just moved some pages from a apachi hosted server onto my nginx install

one page contains the php code

<div id="sectionB">
<object data="<?echo $row->doc;?>"
type="application/pdf"
width="100%"
height="100%">
</object>
</div>

in the apachi server this would open a frame and display the pdf file for which the URL was in $row (offsite url if thats significant)

in nginx .... nothing , no content, no frame , nada

do i maby need some lines in sites-availiable or something?

Thanks for any light anyone can shed on possible reasons :)