Weird breaking animation on a custom-rendered block

[voidzm]

I have a block that I am working on that uses an ISimpleBlockRenderingHandler for a custom appearance. There are no problems with the rendering itself, but whenever I try to break the block, the two different textures that are drawn in the block light up with the breaking texture for their counterparts in the default "terrain.png" texture sheet. This doesn't happen with regular blocks that don't use a custom renderer.

 

To clarify that, if I have part of my block drawing the 32nd texture from my preloaded mod texture sheet, while I'm breaking it it shows a pale highlight of the Gold Ore texture, which occupies slot 32 on the default sheet.

 

I'm looking for a way to either redirect the breaking overlay to my texture sheet or disable the breaking animation altogether. I poked around in the code a little and as far as I could tell the "terrain.png" link is hardcoded into the breaking render function, so I may only be able to disable it...