Hey Fellow minecraftians.

I Have decided to make my next mod with Modloader, and so have made a test mod to get familliar with modloader.
I have succsessfully created two npc's, some items and some blocks. However, with the biome i am having problems. I have sucsessfully made the biome, but whenever i set The topBlock and fillerBlock to a custom block that i made, i get the following error message: http://pastebin.com/Whd22u8m

Here are all of the files in BiomeGenCorruption: http://pastebin.com/nSzeDAVB

And here are the files related to biome generation in mod_Corruption: http://pastebin.com/EJ9sXL8z


And here are the files relating to the blocks i am setting as the Blocks in the biome:

Corrupt Dirt
http://pastebin.com/8R6tXAYB

Corrupt Grass
http://pastebin.com/x23dPdYk


And finally, here are any files in mod_Corruption relating to those blocks.
http://pastebin.com/LeZbLBJC


Thank you for any help given, i really appreciate it as this is the first time i have used modloader.
Thanks