Like the title says and here is the crash report http://pastebin.com/mGzT2Qvf

This does not happen with BuildCraft 6.3.1 and earlier versions . BTW I don't know if this is on your end or AM2 so I am posting this report on both GitHubs

Fixed in BC 6.3.3. I hope.

I also fixed the update code from 6.2 -> 6.3. Turns out I screwed up badly.

Thanks this fixed it. :) Thank you very much!