Does anyone got an Idea how to fix this?

Whenever I put an obsidian Sword or Paxel in an anvil with an enchanted Book, the game crash. Server still fine tho.

I'm using Mekanism-1.7.10-7.1.0.92 on forge-1.7.10-10.13.0.1208

Here's the report
http://pastebin.com/raw.php?i=gTR2MvNV

TY very much =)

Well after a few reading I tried to remove Mine&Blade Battlegear from my mod list and it works fine now. That mod adds enchanting recipes... thats the only link with this bug i can think of.

Do you know if you can do anything about this? I'd love to keep both mods of course...

Mine&Blade Battlegear link below.
(http://www.minecraftforum.net/forums/mapping-and-modding/minecraft-mods/1291267-mine-blade-battlegear-2-bullseye-1-0-6-1#FAQ)

I just posted an Issue on the Github of Mine&Blade Battlegear as well.
Mine-and-blade-admin/Battlegear2#134

Hope you guys can work this out ;)

I received this answer from the Mine&Blade Battlegear admin:

"GotoLink commented 4 hours ago
I don't see how this could be related to our mod at any point. We don't influence Item.ToolMaterial, which is what is failing here.
Looking at Mekanism repo, they didn't set Item.ToolMaterial#customCraftingMaterial.
Which means invalid ItemStack here
Thus books are invalid on anvil for Mekanism tools."

I really don't think this has to do with Mekanism, and if it did there's really nothing I could do about it. I'll try to communicate with the Battlegear team to see what they can do.