Very late answer to this, but just getting around to updating my own mod. Found the answer my usual method, when I can't find the answer quickly on the forums, I usually go to the original class where it came from, in this case, SlotFurnace, which is under net.minecraft.inventory.
It appears this no longer falls under Game Registry, and is now part of FMLCommonHandler:
Robbi Blechdose
GameRegistry.onItemSmelted(thePlayer, par1ItemStack);
Very late answer to this, but just getting around to updating my own mod. Found the answer my usual method, when I can't find the answer quickly on the forums, I usually go to the original class where it came from, in this case, SlotFurnace, which is under net.minecraft.inventory.
It appears this no longer falls under Game Registry, and is now part of FMLCommonHandler:
FMLCommonHandler.instance().firePlayerSmeltedEvent(thePlayer, par1ItemStack);