Help! Massivecore BUG?

[FreeNightYT]

I have a problem. (Spigot Server 1.8)

[Server] ERROR Plugin MassiveCore v2.14.0 has failed to register events for class com.massivecraft.massivecore.item.WriterItemStackMeta because org/bukkit/inventory/meta/BlockStateMeta does not exist.
[Server] ERROR Plugin MassiveCore v2.14.0 has failed to register events for class com.massivecraft.massivecore.item.WriterItemStackMetaBannerPatterns because org/bukkit/inventory/meta/BlockStateMeta does not exist.
[Server] ERROR Plugin MassiveCore v2.14.0 has failed to register events for class com.massivecraft.massivecore.item.WriterItemStackMetaBannerBase because org/bukkit/inventory/meta/BlockStateMeta does not exist.
[Server] ERROR Plugin MassiveCore v2.14.0 has failed to register events for class com.massivecraft.massivecore.item.WriterItemStackMetaFlags because org/bukkit/inventory/meta/BlockStateMeta does not exist.
[Server] ERROR Plugin MassiveCore v2.14.0 has failed to register events for class com.massivecraft.massivecore.item.WriterItemStackMetaUnbreakable because org/bukkit/inventory/meta/BlockStateMeta does not exist.
[Server] ERROR Plugin MassiveCore v2.14.0 has failed to register events for class com.massivecraft.massivecore.item.WriterItemStackMetaStoredEnchants because org/bukkit/inventory/meta/BlockStateMeta does not exist.
[Server] ERROR Plugin MassiveCore v2.14.0 has failed to register events for class com.massivecraft.massivecore.item.WriterItemStackMetaFireworkFlight because org/bukkit/inventory/meta/BlockStateMeta does not exist.
[Server] ERROR Plugin MassiveCore v2.14.0 has failed to register events for class com.massivecraft.massivecore.item.WriterItemStackMetaFireworkEffects because org/bukkit/inventory/meta/BlockStateMeta does not exist.
[Server] ERROR Plugin MassiveCore v2.14.0 has failed to register events for class com.massivecraft.massivecore.item.WriterItemStackMetaFireworkEffect because org/bukkit/inventory/meta/BlockStateMeta does not exist.
[Server] ERROR Plugin MassiveCore v2.14.0 has failed to register events for class com.massivecraft.massivecore.item.WriterItemStackMetaSkull because org/bukkit/inventory/meta/BlockStateMeta does not exist.
[Server] ERROR Plugin MassiveCore v2.14.0 has failed to register events for class com.massivecraft.massivecore.item.WriterItemStackMetaPotionEffects because org/bukkit/inventory/meta/BlockStateMeta does not exist.
[Server] ERROR Plugin MassiveCore v2.14.0 has failed to register events for class com.massivecraft.massivecore.item.WriterItemStackMetaScaling because org/bukkit/inventory/meta/BlockStateMeta does not exist.
[Server] ERROR Plugin MassiveCore v2.14.0 has failed to register events for class com.massivecraft.massivecore.item.WriterItemStackMetaColor because org/bukkit/inventory/meta/BlockStateMeta does not exist.
[Server] ERROR Plugin MassiveCore v2.14.0 has failed to register events for class com.massivecraft.massivecore.item.WriterItemStackMetaPages because org/bukkit/inventory/meta/BlockStateMeta does not exist.
[Server] ERROR Plugin MassiveCore v2.14.0 has failed to register events for class com.massivecraft.massivecore.item.WriterItemStackMetaAuthor because org/bukkit/inventory/meta/BlockStateMeta does not exist.
[Server] ERROR Plugin MassiveCore v2.14.0 has failed to register events for class com.massivecraft.massivecore.item.WriterItemStackMetaTitle because org/bukkit/inventory/meta/BlockStateMeta does not exist.
[Server] ERROR Plugin MassiveCore v2.14.0 has failed to register events for class com.massivecraft.massivecore.item.WriterItemStackMetaRepaircost because org/bukkit/inventory/meta/BlockStateMeta does not exist.
[Server] ERROR Plugin MassiveCore v2.14.0 has failed to register events for class com.massivecraft.massivecore.item.WriterItemStackMetaEnchants because org/bukkit/inventory/meta/BlockStateMeta does not exist.
[Server] ERROR Plugin MassiveCore v2.14.0 has failed to register events for class com.massivecraft.massivecore.item.WriterItemStackMetaLore because org/bukkit/inventory/meta/BlockStateMeta does not exist.
[Server] ERROR Plugin MassiveCore v2.14.0 has failed to register events for class com.massivecraft.massivecore.item.WriterItemStackMetaName because org/bukkit/inventory/meta/BlockStateMeta does not exist.