PDF vs Flashpaper

I successfully created a report with the CF report builder. The format that I originally used in the <cfreport> tag was pdf, but I opted to switch to flashpaper after experiencing how long it takes to launch Acrobat. Nor do I like to see the window cluttered with all of the Actobat controls. Flashpaper is simpler and cleaner for this particular report application.

The problem I am experiencing is that the report will show up in MS IE7 only if I use the pdf format. Mozilla and Opera browsers have no problem with the flashpaper format. Anyone have an answer to why IE does not handle it? Thanks!