Goo-Gone. If you can't find any in your area, look for a product sold as a degreaser, or a POG (paint, oil & grease remover). I use Goo-Gone for chewing gum, candle wax, crayons, oil/grease stains, etc.
I've had success with a product called Orange Sol. Similar I imagine to goo-gone but is claimed to be organic, all-natural and safe. Both smell like orange oil though. orange-sol.com I believe.