Wearing a Wolf Traveller's Backpack durring a full moon on a server disconnects it's wearer with the error "Internal server error". I believe it's caused by the Backpack's ability to be called wrongly. This bug does not occur on Single player.

Forge Version: 14.23.5.2847 (Both server and client)

On the server's log, this log can be found. : Pastebin here

Mod list: Mod list here