Ok, it works on my other world, which has like no plugins. I'll go through all my plugins to see which one it is, then announce it. Whatever 104 and 136 source files are...0_o EDIT by Moderator: merged posts, please use the edit button instead of double posting.
950 is already out but there are still bugs. Place a piston next to its own power supply so that it cuts it off and watch your server die. Even if you restart it instantly kills itself again. You have to revert back to 1.6 and go in to remove the piston block before you can get it running again. Best to wait for a RB.