Is present in first beta, and is also present in 1017 beta.

http://pastie.org/private/xvb7vmzuhucbpxenbkpzq
http://pastie.org/private/pjtufde1cj6s4efuoaw1a

It's a sponge bug. IronChest is registering multiple TE names (old ones, for backwards compatibility).

clazz is null

WOOD(0, 0, false, "", "", -1, Arrays.asList("plankWood"), null);

https://github.com/progwml6/ironchest/blob/master/src/main/java/cpw/mods/ironchest/IronChestType.java#L37

@cpw The question is why IronChest is trying to register a null Class<? extends TileEntity> here, because that's what Sponge is capturing and failing (for obvious reasons). So please, clarify for me here where Sponge is breaking contract?

@cpw could you please enlighten this problem as I still need this fixed...

@Mickimoo2 this can be closed now, the latest SpongeForge will appropriately handle cases like these.

Okay, thank you gabizou.