ItemBlock now implements ITextureProvider so that blocks with custom textures will showup properly when being held.

forge/patches/minecraft/net/minecraft/src/ItemBlock.java.patch

@@ -0,0 +1,30 @@
+--- ../src_base/minecraft/net/minecraft/src/ItemBlock.java	0000-00-00 00:00:00.000000000 -0000
++++ ../src_work/minecraft/net/minecraft/src/ItemBlock.java	0000-00-00 00:00:00.000000000 -0000
+@@ -1,6 +1,8 @@
+ package net.minecraft.src;
+ 
+-public class ItemBlock extends Item
++import net.minecraft.src.forge.ITextureProvider;
++
++public class ItemBlock extends Item implements ITextureProvider
+ {
+     /** The block ID of the Block associated with this ItemBlock */
+     private int blockID;
+@@ -110,4 +112,17 @@
+     {
+         return Block.blocksList[this.blockID].getBlockName();
+     }
++
++    @Override
++    public String getTextureFile() 
++    {
++        if (Block.blocksList[blockID] instanceof ITextureProvider)
++        {
++            return ((ITextureProvider)Block.blocksList[blockID]).getTextureFile();
++        }
++        else
++        {
++            return "/terrain.png";
++        }
++    }
+ }