I'm having the same problem.
On my Windows 7 64bit, the page that works well in both Chrome and Firefox has some strange issues on IE9.
The page is:
Actually, the strange thing is that the PDF appears, thanks to the block:
<object width="70%" height="500" class="pdf ie" data="http://ict.ing.unimo.it/telecom_lab/wp-content/uploads/2012/10/indoor_positioning_research_activity_2012.pdf" type="application/pdf">
but then, just below that block I see:
<div style="width: 70%; height: 500px; ...;">
Unable to display PDF
Click here to download
which of course takes 500px away! Note that 500px is the width I used for embedding the pdf.
I will try to debug this, if I have time. In the meanwhile, any help would be appreciated :)