PHP affecting PDF plug-in....?

All... I have a PDF plug-in problem... Now before you say anything the problem doesnt exesi when I remove PHP from the equation... I have a script that generates a drop-down list of ID's basically... Clicking continue will pass the ID to a script which I use to get the correct filename to display... ALSO, this only seems to happen on IE 5... This is what happens... 1) login 2) select option to display list... 3) Select Item... 4) Pass & display item 5) select option to display list... 6) Select Item... 7) Pass & display item Now... at stage 7... is where it appears to go wrong... i.e. IE hangs.... The PDF file is being displayed via an <iframe>, also note that if I remove the <iframe> the flow is as normal... [ http://www.the-local-guide.com :: http://www.mcgarvie.net ]