I installed the plugin in my server (1.23 version) but it wont start and shares me this error.

[14:11:04 ERROR]: [PermissionsEx] Error occurred with PermissionsEx! Please post it to http://git.io/vEZl1. Full error:
java.lang.NoSuchMethodError: com.google.common.cache.CacheBuilder.maximumSize(J)Lcom/google/common/cache/CacheBuilder;
at ru.tehkode.permissions.RegExpMatcher.(RegExpMatcher.java:17)
at ru.tehkode.permissions.PermissionManager.(PermissionManager.java:58)
at ru.tehkode.permissions.bukkit.PermissionsEx.onEnable(PermissionsEx.java:164)
at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:316)
at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:332)
at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:417)
at org.bukkit.craftbukkit.v1_7_R4.CraftServer.loadPlugin(CraftServer.java:476)
at org.bukkit.craftbukkit.v1_7_R4.CraftServer.enablePlugins(CraftServer.java:394)
at net.minecraft.server.v1_7_R4.MinecraftServer.n(MinecraftServer.java:360)
at net.minecraft.server.v1_7_R4.MinecraftServer.g(MinecraftServer.java:334)
at net.minecraft.server.v1_7_R4.MinecraftServer.a(MinecraftServer.java:290)
at net.minecraft.server.v1_7_R4.DedicatedServer.init(DedicatedServer.java:210)
at net.minecraft.server.v1_7_R4.MinecraftServer.run(MinecraftServer.java:458)
at net.minecraft.server.v1_7_R4.ThreadServerApplication.run(SourceFile:628)
[14:11:04 INFO]: [PermissionsEx] Disabling PermissionsEx v1.23

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