Super Glue is not a good lubricant!
Although I highly do not recommend it, acetone is just about the only thing I know of that will weaken the bond of the superglue. It will also slowly attack most plastics (and completely dissolves Styrofoam), so if you you should decide to use acetone to break the glue, immediately wash the parts with alcohol when done. Use only as a last resort. I take no responsibility if you ruin your cube!
My Creepy 3D Rubik's Cube Video
Yeah, Uwe is Dalai Lama and Paganotis is mother Teresa of Calcutta.