I think that there is generally nothing wrong with PDFBox itself, but with the ImageIO.read which just refuses to recognize PNG files as transparent(PDImageXObject.create* uses the ImageIO.read too.). I had to use the workaround I described in here http://stackoverflow.com/questions/18743790/can-java-load-images-with-transparency/39826953#39826953
I am not using outlook, I just use the PonyMail to view the thread and there I click on reply to respond via gmail in a browser.
