Erreur au lancement

Salut !
J'ai un soucis avec le plugin Shop, je l'utilise actuellement sur sa dernière version, regardez ici : http://dev.bukkit.or...-plugins/shops/
Quand j'installe le plugin et que je lance le serveur, aucun problème, moi et mes amis on à créé environ 15 shops.
Je restart mon serveur sans avoir installé ni modifié quoi que ce soit en plus, et surprise ! Tous les shops sont HS, les panneaux sont devenus vierges et seul un shop n'a pas été affecté, allez savoir pourquoi... Logs d'erreurs :
[23:58:27] [Server thread/INFO]: [Shop] Enabling Shop v1.4.8
[23:58:27] [Server thread/INFO]: [Shop] Shops will use emerald as the currency on the server.
[23:58:28] [Server thread/ERROR]: Error occurred while enabling Shop v1.4.8 (Is it up to date?)
java.lang.NullPointerException
at org.bukkit.craftbukkit.v1_7_R1.block.CraftSign.<init>(CraftSign.java:17) ~[craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
at org.bukkit.craftbukkit.v1_7_R1.block.CraftBlock.getState(CraftBlock.java:252) ~[craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
at com.snowgears.shop.ShopHandler.loadShopsFromConfig(ShopHandler.java:211) ~[?:?]
at com.snowgears.shop.ShopHandler.loadShops(ShopHandler.java:195) ~[?:?]
at com.snowgears.shop.Shop.onEnable(Shop.java:147) ~[?:?]
at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:250) ~[craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:350) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:389) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
at org.bukkit.craftbukkit.v1_7_R1.CraftServer.loadPlugin(CraftServer.java:439) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
at org.bukkit.craftbukkit.v1_7_R1.CraftServer.enablePlugins(CraftServer.java:375) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
at net.minecraft.server.v1_7_R1.MinecraftServer.m(MinecraftServer.java:342) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
at net.minecraft.server.v1_7_R1.MinecraftServer.g(MinecraftServer.java:319) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
at net.minecraft.server.v1_7_R1.MinecraftServer.a(MinecraftServer.java:275) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
at net.minecraft.server.v1_7_R1.DedicatedServer.init(DedicatedServer.java:175) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
at net.minecraft.server.v1_7_R1.MinecraftServer.run(MinecraftServer.java:424) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
at net.minecraft.server.v1_7_R1.ThreadServerApplication.run(SourceFile:617) [craftbukkit-1.7.2-R0.3.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
[23:58:28] [Server thread/INFO]: [iDisguise] Enabling iDisguise v3.0.3


Tous les shops ont disparu du fichier qui les gère, soit shops.yml. Sur mon serveur, voici mes plugins : Orebfuscator, BetterReload, WorldEdit, NoCheatPlus, Vault, Multiverse-Core, PermissionsEx, Vote, MyCommand, Prism, WorldGuard, dynmap, AutoMessage, iConomy, BasicMaintenance, Shop, iDisguise, Lockette, Modifyworld, CleanroomGenerator, KillsPay, Essentials, EssentialsSpawn, Multiverse-Portals, Multiverse-Inventories, xAuth, EssentialsChat.

Merci d'avance pour votre aide.. :/