Preparation Hell!

I have managed to remove an old paper border from 2 walls. But I can't for love nor money get rid of the adhesive. I have tried the steamer, wallpaper stripper, sticky stuff remover, nail varnish remover and acetone (these last 3 melted the scourer but had no effect on the glue). I am now stuck (no pun intended) although a friend says to try a hairdryer on its hottest setting.