I don't know about a paper background, but I've heard of people doing that to keep a plastic one "stuck" to the back of the glass (though you still have to secure it with tape or whatever). The idea is to prevent the 'bubbles' that you often get with such backgrounds. IMHO it wouldn't be worth the hassle or mess.
-Rick (the armchair aquarist, who's opinion is worth exactly what you paid for it)
Make sure that your the edges of the background is cut accurately. I found this out the hardway. For over an hour I could not get it to go on without issues. Once I straightened out the edges it went on very easily.