So I made the Backhouse Family fruitcake from Martha Stewart Living a few years ago. I made it a couple Christmases ago, and it went great--moist and rich and all that, and it stayed good, wrapped in plastic wrap, for about two weeks. This time, something went horribly wrong! I wrapped it in cheesecloth and sprinkled it with rum when it was cool, then I put it in a plastic container and took it out a week later to sprinkle it again. It smelled great, and I put it away again. But the next day, when I took it out to serve, it was soggy, and it smelled kind of sour and spoiled--so bad, in fact, that I had to throw it away. I figure that it had something to do with the container I had it in, and the rum's not evaporating; was it mold? Or rot? Or what kind of spoilage? Has anybody else ever had this happen?