There was a guy at the Knoxville show several years ago who would punch a screwdriver thru the bottom of an aluminum soda can, then proceed to repair the hole with a propane torch and a special type of welding rod he was selling. He made it look quite easy, so I'm sure it can be repaired. That said, if I were going to repair it, I would use a dab of epoxy after cleaning it to bright metal. The problem with heating/repairing aluminum, especially thin aluminum, is that the way you can tell when you get it too hot is that it will "fall away" or melt. There's no warning, it doesn't change color like steel before melting.
I wouldn't bother repairing it - the aluminum is pretty thin to begin with, and if you got one pinhole, more are coming, soon. Call Tom DeWitt and get a new one - I spent most of Saturday in his shop, and he's making lots of them.