I tried that very first, and it would work if it wasn't because you had to overwrite the vanilla recipes with the Ore Dictionary word for leather
i have a solution here
[sOLVED]
I simple added the code itself inside the Ore Dictionary
registerOre("itemLeather", Item.leather);
under the other registerOre lines
and then under
replacements.put(new ItemStack(Item.stick), "stickWood");
i added
replacements.put(new ItemStack(Item.leather), "itemLeather");
when compiling you will get two file in net\minecraftforge\oredict
thouse should be added inside the minecraft.jar
then you simple load you mod as normal and everything runs smoothly
and when forge comes with an update for the leather you simple skip that step