Board Thread:Questions and Answers/@comment-90.219.128.7-20130211221633/@comment-6024139-20130214193037

Ok, it looks like some mods aren't done in the default texturepack. IronChests is a part of Tekkit. Tekkit is just a collection of different mods. You have to add them to the texturepack yourself.

Here, for example, is a patch to include the IronChests mod. You can probably look around that site for more patches for other mods.