Got a server-side NPE today that did not crash the server entirely, but left it unresponsive until I had to force-kill it. Not sure what caused it, but Roguelike is mentioned.

Forge-965
Roguelike version 1.6.4-1.3.0

Portion of log from ForgeModLoader: http://pastebin.com/Ar1K24v7
Full ForgeModLoader-server log https://dl.dropboxusercontent.com/u/130875325/Minecraft/ForgeModLoader-server-1.log
There's nothing at all in server.log about it.

Thanks, it seems like the server crashed while attempting to set the rotation of a skull in the ossuary. I suspect it's because the block wasn't actually a skull and I didn't check to make sure.

it must be a super rare situation but I might be able to fix it by adding in some extra sanity checks.

I believe this problem fixed in the latest update. I added a check to make sure that placing the skull succeeded before trying to rotate it.