I've tried with MCP and ModLoad an item and a ladder programming. I entered this code: package net.minecraft.src;
import net.minecraft.client.Minecraft;

public class test extends BaseMod
{
public static Item test1 = new Item(520).setItemName("test1");
public static Block test2 = (new BlockLadder(0, 0)).setHardness(0.4F).setBlockName("test2").setRequiresSelfNotify();

public void load()
{
test1.iconIndex = ModLoader.addOverride("/gui/items.png", "/test1.png");
ModLoader.AddName(nstick, "test1");

ModLoader.RegisterBlock(test2);
test2.blockIndexInTexture = ModLoader.addOverride("/terrain.png", "/test2.png");
ModLoader.AddName(test2, "test2");

}

public String getVersion() {
return "1.0.0";
}

}

I can recompile it and run the client, but if I try to open a world, minecraft run out of memory and crash.

NEED HELP !!

GermanModders