setContainerItem doesn't work for me (neither does CraftingHandler)

Hi everyone,

I tried to make a small Mod that features Bio Gas and Bio Gas Container.

By putting the Bio Gas into a Crafting grid you're supposed to craft some Fuel. However, I can craft the coal (Currently it's coal) without problems, BUT the Bio Gas Container will just be consumed:

Main mod.class: (relevant things)

public static Item BioGas;
public static Item EmptyGas;

@Init
public void load(FMLInitializationEvent event)
{
	this.BioGas = new BioGas(2453).setContainerItem(this.EmptyGas);
	this.EmptyGas = new BioGas(2454);

	GameRegistry.addShapelessRecipe(new ItemStack(Item.coal,1), new Object[]{
		this.BioGas
	});
}

The BioGas class looks like this:

public class BioGas extends Item {

public BioGas(int par1) {
	super(par1);
	this.setCreativeTab(CreativeTabs.tabMaterials);
}

}

I also tried creating a CraftingHandler, but it won't work.

I hope someone can help me

Thank you!