Errors

Caused by: java.lang.RuntimeException: Permissions manager is not accessable. Is the PermissionsEx plugin enabled?
	at ru.tehkode.permissions.bukkit.PermissionsEx.getPermissionManager(PermissionsEx.java:148)
	at com.palmergames.bukkit.towny.permissions.PEXSource.hasPermission(PEXSource.java:140)
	at com.palmergames.bukkit.towny.object.CachePermissions.getPermission(CachePermissions.java:251)
	at com.palmergames.bukkit.towny.object.CachePermissions.triggerCacheCreate(CachePermissions.java:78)
	at com.palmergames.bukkit.towny.object.CachePermissions.getCachePermission(CachePermissions.java:57)
	at com.palmergames.bukkit.towny.event.TownyBlockListener.onBlockPlace(TownyBlockListener.java:183)
	... 19 more
2012-03-30 23:32:22 [SEVERE] Could not pass event org.bukkit.event.block.BlockPlaceEvent to Towny
org.bukkit.event.EventException
	at org.bukkit.plugin.java.JavaPluginLoader$103.execute(JavaPluginLoader.java:1026)
	at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:61)
	at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:460)
	at org.bukkit.craftbukkit.event.CraftEventFactory.callBlockPlaceEvent(CraftEventFactory.java:109)
	at org.bukkit.craftbukkit.event.CraftEventFactory.callBlockPlaceEvent(CraftEventFactory.java:93)
	at buildcraft.factory.TileQuarry.doWork(TileQuarry.java:203)
	at buildcraft.api.PowerProvider.update(PowerProvider.java:52)
	at buildcraft.core.TileBuildCraft.l_(TileBuildCraft.java:51)
	at buildcraft.factory.TileQuarry.l_(TileQuarry.java:132)
	at net.minecraft.server.World.tickEntities(World.java:1182)
	at net.minecraft.server.MinecraftServer.w(MinecraftServer.java:534)
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:441)
	at net.minecraft.server.ThreadServerApplication.run(SourceFile:465)
Caused by: java.lang.reflect.InvocationTargetException
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
	at java.lang.reflect.Method.invoke(Unknown Source)
	at org.bukkit.plugin.java.JavaPluginLoader$103.execute(JavaPluginLoader.java:1024)
	... 12 more
Caused by: java.lang.RuntimeException: Permissions manager is not accessable. Is the PermissionsEx plugin enabled?
	at ru.tehkode.permissions.bukkit.PermissionsEx.getPermissionManager(PermissionsEx.java:148)
	at com.palmergames.bukkit.towny.permissions.PEXSource.hasPermission(PEXSource.java:140)
	at com.palmergames.bukkit.towny.object.CachePermissions.getPermission(CachePermissions.java:251)
	at com.palmergames.bukkit.towny.object.CachePermissions.triggerCacheCreate(CachePermissions.java:78)
	at com.palmergames.bukkit.towny.object.CachePermissions.getCachePermission(CachePermissions.java:57)
	at com.palmergames.bukkit.towny.event.TownyBlockListener.onBlockPlace(TownyBlockListener.java:183)
	... 17 more