I didn't found any problem in-game, but in server log is
"[11:52:31] [Server thread/ERROR]: Module loading failed for class class mods.natura.plugins.nei.NotEnoughItems; a referenced class is missing."
I have these mods on the server:
[email protected],[email protected],[email protected],[email protected],[email protected],MineFactoryReloaded|[email protected],[email protected],MineFactoryReloaded|[email protected],MineFactoryReloaded|[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],ProjRed|[email protected],[email protected],[email protected],appliedenergistics2-core@rv1-beta-18,[email protected],[email protected],ProjRed|[email protected],[email protected],MineFactoryReloaded|[email protected],[email protected],[email protected],[email protected],ProjRed|[email protected],MineFactoryReloaded|[email protected],[email protected],MineFactoryReloaded|[email protected],[email protected],[email protected],[email protected],[email protected],MineFactoryReloaded|[email protected],[email protected],[email protected],[email protected],MineFactoryReloaded|[email protected],[email protected],[email protected],[email protected],MineFactoryReloaded|[email protected],[email protected],[email protected],Ping@%MOD_VERSION,[email protected],[email protected],[email protected],[email protected],MineFactoryReloaded|[email protected],[email protected],MineFactoryReloaded|[email protected],BuildCraft|[email protected],[email protected],[email protected],[email protected],MineFactoryReloaded|[email protected],[email protected],MineFactoryReloaded|[email protected],[email protected],MineFactoryReloaded|[email protected],[email protected],OpenComputers|[email protected],[email protected],[email protected],ProjRed|[email protected],BuildCraft|[email protected],[email protected],MineFactoryReloaded|[email protected],[email protected],[email protected],BuildCraft|[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],@000,[email protected],appliedenergistics2@rv1-beta-18,MineFactoryReloaded|[email protected],ProjRed|[email protected],[email protected],MineFactoryReloaded|[email protected],BuildCraft|[email protected],[email protected],[email protected],[email protected],[email protected],ProjRed|[email protected],ProjRed|[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],BuildCraft|[email protected],MineFactoryReloaded|[email protected],[email protected],[email protected],ProjRed|[email protected],[email protected],BuildCraft|[email protected],[email protected],MineFactoryReloaded|[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],OpenModsCore@@Version@,[email protected],[email protected],MineTweaker3@${version},[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected]

please post the entire FML log

Im sorry, but no longer have this error cuz I have installed NEI to server and error disapeared. Looks like that NEI is needed for this mod (on server too) for correct function (wothout errors).